diff --git a/cof/urls.py b/cof/urls.py
index 7ec728da..06b1087a 100644
--- a/cof/urls.py
+++ b/cof/urls.py
@@ -84,7 +84,7 @@ urlpatterns = [
     url(r'^k-fet/', include('kfet.urls')),
 ]
 
-if settings.DEBUG:
+if 'debug_toolbar' in settings.INSTALLED_APPS:
     import debug_toolbar
     urlpatterns += [
         url(r'^__debug__/', include(debug_toolbar.urls)),
diff --git a/kfet/models.py b/kfet/models.py
index c039ab06..6ddac84d 100644
--- a/kfet/models.py
+++ b/kfet/models.py
@@ -491,24 +491,29 @@ class TransferGroup(models.Model):
         related_name = "+",
         blank = True, null = True, default = None)
 
+
 class Transfer(models.Model):
     group = models.ForeignKey(
-        TransferGroup, on_delete = models.PROTECT,
-        related_name = "transfers")
+        TransferGroup, on_delete=models.PROTECT,
+        related_name="transfers")
     from_acc = models.ForeignKey(
-        Account, on_delete = models.PROTECT,
-        related_name = "transfers_from")
+        Account, on_delete=models.PROTECT,
+        related_name="transfers_from")
     to_acc = models.ForeignKey(
-        Account, on_delete = models.PROTECT,
-        related_name = "transfers_to")
-    amount = models.DecimalField(max_digits = 6, decimal_places = 2)
+        Account, on_delete=models.PROTECT,
+        related_name="transfers_to")
+    amount = models.DecimalField(max_digits=6, decimal_places=2)
     # Optional
     canceled_by = models.ForeignKey(
-        Account, on_delete = models.PROTECT,
-        null = True, blank = True, default = None,
-        related_name = "+")
+        Account, on_delete=models.PROTECT,
+        null=True, blank=True, default=None,
+        related_name="+")
     canceled_at = models.DateTimeField(
-        null = True, blank = True, default = None)
+        null=True, blank=True, default=None)
+
+    def __str__(self):
+        return '{} -> {}: {}€'.format(self.from_acc, self.to_acc, self.amount)
+
 
 class OperationGroup(models.Model):
     on_acc = models.ForeignKey(
diff --git a/kfet/static/kfet/css/index.css b/kfet/static/kfet/css/index.css
index 5a82b5cf..f21fdaba 100644
--- a/kfet/static/kfet/css/index.css
+++ b/kfet/static/kfet/css/index.css
@@ -106,6 +106,7 @@ textarea {
 
 .panel-md-margin{
     background-color: white;
+    overflow:hidden;
     padding-left: 15px;
     padding-right: 15px;
     padding-bottom: 15px;
diff --git a/kfet/static/kfet/js/statistic.js b/kfet/static/kfet/js/statistic.js
index 7ab56f1d..f210c11d 100644
--- a/kfet/static/kfet/js/statistic.js
+++ b/kfet/static/kfet/js/statistic.js
@@ -1,10 +1,10 @@
 (function($){
     window.StatsGroup = function (url, target) {
         // a class to properly display statictics
-        
+
         // url : points to an ObjectResumeStat that lists the options through JSON
         // target : element of the DOM where to put the stats
-        
+
         var self = this;
         var element = $(target);
         var content = $("<div>");
@@ -22,28 +22,29 @@
             return array;
         }
 
-        function handleTimeChart (dict) {
+        function handleTimeChart (data) {
             // reads the balance data and put it into chartjs formatting
-            var data = dictToArray(dict, 0);
+            chart_data = new Array();
             for (var i = 0; i < data.length; i++) {
                 var source = data[i];
-                data[i] = { x: new Date(source.at),
-                            y: source.balance,
-                            label: source.label }
+                chart_data[i] = {
+                    x: new Date(source.at),
+                    y: source.balance,
+                    label: source.label,
+                }
             }
-            return data;
+            return chart_data;
         }
-        
+
         function showStats () {
             // CALLBACK : called when a button is selected
-            
+
             // shows the focus on the correct button
             buttons.find(".focus").removeClass("focus");
             $(this).addClass("focus");
 
             // loads data and shows it
-            $.getJSON(this.stats_target_url + "?format=json",
-                      displayStats);
+            $.getJSON(this.stats_target_url, {format: 'json'}, displayStats);
         }
 
         function displayStats (data) {
@@ -51,14 +52,14 @@
 
             var chart_datasets = [];
             var charts = dictToArray(data.charts);
-            
+
             // are the points indexed by timestamps?
             var is_time_chart = data.is_time_chart || false;
 
             // reads the charts data
             for (var i = 0; i < charts.length; i++) {
                 var chart = charts[i];
-                
+
                 // format the data
                 var chart_data =  is_time_chart ? handleTimeChart(chart.values) : dictToArray(chart.values, 1);
 
@@ -78,6 +79,7 @@
             var chart_options =
                 {
                     responsive: true,
+                    maintainAspectRatio: false,
                     tooltips: {
                         mode: 'index',
                         intersect: false,
@@ -130,25 +132,25 @@
                     type: 'line',
                     options: chart_options,
                     data: {
-                        labels: dictToArray(data.labels, 1),
+                        labels: (data.labels || []).slice(1),
                         datasets: chart_datasets,
                     }
                 };
 
             // saves the previous charts to be destroyed
             var prev_chart = content.children();
-            
+
+            // clean
+            prev_chart.remove();
+
             // creates a blank canvas element and attach it to the DOM
-            var canvas = $("<canvas>");
+            var canvas = $("<canvas height='250'>");
             content.append(canvas);
 
             // create the chart
             var chart = new Chart(canvas, chart_model);
-            
-            // clean
-            prev_chart.remove();
         }
-        
+
         // initialize the interface
         function initialize (data) {
             // creates the bar with the buttons
@@ -158,8 +160,8 @@
                          "aria-label": "select-period"});
 
             var to_click;
-            var context = dictToArray(data.stats);
-            
+            var context = data.stats;
+
             for (var i = 0; i < context.length; i++) {
                 // creates the button
                 var btn_wrapper = $("<div>",
@@ -191,7 +193,7 @@
 
         // constructor
         (function () {
-            $.getJSON(url + "?format=json", initialize);
+            $.getJSON(url, {format: 'json'}, initialize);
         })();
     };
 })(jQuery);
diff --git a/kfet/statistic.py b/kfet/statistic.py
index 09f9e935..fe948f73 100644
--- a/kfet/statistic.py
+++ b/kfet/statistic.py
@@ -1,98 +1,155 @@
 # -*- coding: utf-8 -*-
+
+from datetime import date, datetime, time, timedelta
+
+from dateutil.relativedelta import relativedelta
+from dateutil.parser import parse as dateutil_parse
+
 from django.utils import timezone
 from django.db.models import Sum
 
-KFET_WAKES_UP_AT = 7
-
-# donne le nom des jours d'une liste de dates
-# dans un dico ordonné
-def daynames(dates):
-    names = {}
-    for i in dates:
-        names[i] = dates[i].strftime("%A")
-    return names
+KFET_WAKES_UP_AT = time(7, 0)
 
 
-# donne le nom des semaines une liste de dates
-# dans un dico ordonné
-def weeknames(dates):
-    names = {}
-    for i in dates:
-        names[i] = dates[i].strftime("Semaine %W")
-    return names
+def kfet_day(year, month, day, start_at=KFET_WAKES_UP_AT):
+    """datetime wrapper with time offset."""
+    return datetime.combine(date(year, month, day), start_at)
 
 
-# donne le nom des mois d'une liste de dates
-# dans un dico ordonné
-def monthnames(dates):
-    names = {}
-    for i in dates:
-        names[i] = dates[i].strftime("%B")
-    return names
+def to_kfet_day(dt, start_at=KFET_WAKES_UP_AT):
+    kfet_dt = kfet_day(year=dt.year, month=dt.month, day=dt.day)
+    if dt.time() < start_at:
+        kfet_dt -= timedelta(days=1)
+    return kfet_dt
 
 
-# rend les dates des nb derniers jours
-# dans l'ordre chronologique
-# aujourd'hui compris
-# nb = 1 : rend hier
-def lastdays(nb):
-    morning = this_morning()
-    days = {}
-    for i in range(1, nb+1):
-        days[i] = morning - timezone.timedelta(days=nb - i + 1)
-    return days
+class Scale(object):
+    name = None
+    step = None
+
+    def __init__(self, n_steps=0, begin=None, end=None,
+                 last=False, std_chunk=True):
+        self.std_chunk = std_chunk
+        if last:
+            end = timezone.now()
+
+        if begin is not None and n_steps != 0:
+            self.begin = self.get_from(begin)
+            self.end = self.do_step(self.begin, n_steps=n_steps)
+        elif end is not None and n_steps != 0:
+            self.end = self.get_from(end)
+            self.begin = self.do_step(self.end, n_steps=-n_steps)
+        elif begin is not None and end is not None:
+            self.begin = self.get_from(begin)
+            self.end = self.get_from(end)
+        else:
+            raise Exception('Two of these args must be specified: '
+                            'n_steps, begin, end; '
+                            'or use last and n_steps')
+
+        self.datetimes = self.get_datetimes()
+
+    @staticmethod
+    def by_name(name):
+        for cls in Scale.__subclasses__():
+            if cls.name == name:
+                return cls
+        return None
+
+    def get_from(self, dt):
+        return self.std_chunk and self.get_chunk_start(dt) or dt
+
+    def __getitem__(self, i):
+        return self.datetimes[i], self.datetimes[i+1]
+
+    def __len__(self):
+        return len(self.datetimes) - 1
+
+    def do_step(self, dt, n_steps=1):
+        return dt + self.step * n_steps
+
+    def get_datetimes(self):
+        datetimes = [self.begin]
+        tmp = self.begin
+        while tmp <= self.end:
+            tmp = self.do_step(tmp)
+            datetimes.append(tmp)
+        return datetimes
+
+    def get_labels(self, label_fmt=None):
+        if label_fmt is None:
+            label_fmt = self.label_fmt
+        return [begin.strftime(label_fmt) for begin, end in self]
 
 
-def lastweeks(nb):
-    monday_morning = this_monday_morning()
-    mondays = {}
-    for i in range(1, nb+1):
-        mondays[i] = monday_morning \
-                    - timezone.timedelta(days=7*(nb - i + 1))
-    return mondays
+class DayScale(Scale):
+    name = 'day'
+    step = timedelta(days=1)
+    label_fmt = '%A'
+
+    @classmethod
+    def get_chunk_start(cls, dt):
+        return to_kfet_day(dt)
 
 
-def lastmonths(nb):
-    first_month_day = this_first_month_day()
-    first_days = {}
-    this_year = first_month_day.year
-    this_month = first_month_day.month
-    for i in range(1, nb+1):
-        month = ((this_month - 1 - (nb - i)) % 12) + 1
-        year = this_year + (nb - i) // 12
-        first_days[i] = timezone.datetime(year=year,
-                                          month=month,
-                                          day=1,
-                                          hour=KFET_WAKES_UP_AT)
-    return first_days
+class WeekScale(Scale):
+    name = 'week'
+    step = timedelta(days=7)
+    label_fmt = 'Semaine %W'
+
+    @classmethod
+    def get_chunk_start(cls, dt):
+        dt_kfet = to_kfet_day(dt)
+        offset = timedelta(days=dt_kfet.weekday())
+        return dt_kfet - offset
 
 
-def this_first_month_day():
-    now = timezone.now()
-    first_day = timezone.datetime(year=now.year,
-                                  month=now.month,
-                                  day=1,
-                                  hour=KFET_WAKES_UP_AT)
-    return first_day
+class MonthScale(Scale):
+    name = 'month'
+    step = relativedelta(months=1)
+    label_fmt = '%B'
+
+    @classmethod
+    def get_chunk_start(cls, dt):
+        return to_kfet_day(dt).replace(day=1)
 
 
-def this_monday_morning():
-    now = timezone.now()
-    monday = now - timezone.timedelta(days=now.isoweekday()-1)
-    monday_morning = timezone.datetime(year=monday.year,
-                                       month=monday.month,
-                                       day=monday.day,
-                                       hour=KFET_WAKES_UP_AT)
-    return monday_morning
+def stat_manifest(scales_def=None, scale_args=None, scale_prefix=None,
+                  **other_url_params):
+    if scale_prefix is None:
+        scale_prefix = 'scale_'
+    if scales_def is None:
+        scales_def = []
+    if scale_args is None:
+        scale_args = {}
+    manifest = []
+    for label, cls in scales_def:
+        url_params = {scale_prefix+'name': cls.name}
+        url_params.update({scale_prefix+key: value
+                           for key, value in scale_args.items()})
+        url_params.update(other_url_params)
+        manifest.append(dict(
+            label=label,
+            url_params=url_params,
+        ))
+    return manifest
 
 
-def this_morning():
-    now = timezone.now()
-    morning = timezone.datetime(year=now.year,
-                                month=now.month,
-                                day=now.day,
-                                hour=KFET_WAKES_UP_AT)
-    return morning
+def last_stats_manifest(scales_def=None, scale_args=None, scale_prefix=None,
+                        **url_params):
+    scales_def = [
+        ('Derniers mois', MonthScale, ),
+        ('Dernières semaines', WeekScale, ),
+        ('Derniers jours', DayScale, ),
+    ]
+    if scale_args is None:
+        scale_args = {}
+    scale_args.update(dict(
+        last=True,
+        n_steps=7,
+    ))
+    return stat_manifest(scales_def=scales_def, scale_args=scale_args,
+                         scale_prefix=scale_prefix, **url_params)
 
 
 # Étant donné un queryset d'operations
@@ -100,3 +157,78 @@ def this_morning():
 def tot_ventes(queryset):
     res = queryset.aggregate(Sum('article_nb'))['article_nb__sum']
     return res and res or 0
+
+
+class ScaleMixin(object):
+    scale_args_prefix = 'scale_'
+
+    def get_scale_args(self, params=None, prefix=None):
+        """Retrieve scale args from params.
+
+        Should search the same args of Scale constructor.
+
+        Args:
+            params (dict, optional): Scale args are searched in this.
+                Default to GET params of request.
+            prefix (str, optional): Appended at the begin of scale args names.
+                Default to `self.scale_args_prefix`.
+
+        """
+        if params is None:
+            params = self.request.GET
+        if prefix is None:
+            prefix = self.scale_args_prefix
+
+        scale_args = {}
+
+        name = params.get(prefix+'name', None)
+        if name is not None:
+            scale_args['name'] = name
+
+        n_steps = params.get(prefix+'n_steps', None)
+        if n_steps is not None:
+            scale_args['n_steps'] = int(n_steps)
+
+        begin = params.get(prefix+'begin', None)
+        if begin is not None:
+            scale_args['begin'] = dateutil_parse(begin)
+
+        end = params.get(prefix+'send', None)
+        if end is not None:
+            scale_args['end'] = dateutil_parse(end)
+
+        last = params.get(prefix+'last', None)
+        if last is not None:
+            scale_args['last'] = (
+                last in ['true', 'True', '1'] and True or False)
+
+        return scale_args
+
+    def get_context_data(self, *args, **kwargs):
+        context = super().get_context_data(*args, **kwargs)
+
+        scale_args = self.get_scale_args()
+        scale_name = scale_args.pop('name', None)
+        scale_cls = Scale.by_name(scale_name)
+
+        if scale_cls is None:
+            scale = self.get_default_scale()
+        else:
+            scale = scale_cls(**scale_args)
+
+        self.scale = scale
+        context['labels'] = scale.get_labels()
+        return context
+
+    def get_default_scale(self):
+        return DayScale(n_steps=7, last=True)
+
+    def chunkify_qs(self, qs, scale, field=None):
+        if field is None:
+            field = 'at'
+        begin_f = '{}__gte'.format(field)
+        end_f = '{}__lte'.format(field)
+        return [
+            qs.filter(**{begin_f: begin, end_f: end})
+            for begin, end in scale
+        ]
diff --git a/kfet/templates/kfet/account_read.html b/kfet/templates/kfet/account_read.html
index 50ab7f20..3c2ccbcd 100644
--- a/kfet/templates/kfet/account_read.html
+++ b/kfet/templates/kfet/account_read.html
@@ -13,12 +13,17 @@
 {% if account.user == request.user %}
 <script type="text/javascript" src="{% static 'kfet/js/Chart.bundle.js' %}"></script>
 <script type="text/javascript" src="{% static 'kfet/js/statistic.js' %}"></script>
-<script>
- jQuery(document).ready(function() {
-     var stat_last = new StatsGroup("{% url 'kfet.account.stat.last' trigramme=account.trigramme %}",
-                                    $("#stat_last"));
-     var stat_balance = new StatsGroup("{% url 'kfet.account.stat.balance' trigramme=account.trigramme %}",
-                                       $("#stat_balance"));
+
+<script type="text/javascript">
+$(document).ready(function() {
+    var stat_last = new StatsGroup(
+        "{% url 'kfet.account.stat.operation.list' trigramme=account.trigramme %}",
+        $("#stat_last"),
+    );
+    var stat_balance = new StatsGroup(
+        "{% url 'kfet.account.stat.balance.list' trigramme=account.trigramme %}",
+        $("#stat_balance"),
+    );
  });
 </script>
 {% endif %}
@@ -66,22 +71,22 @@
       {% if account.user == request.user %}
       <div class="content-right-block content-right-block-transparent">
         <h2>Statistiques</h2>
-	<div class="row">
-            <div class="col-sm-12 nopadding">	
-                <div class="panel-md-margin">
-                    <h3>Ma balance</h3>
-                    <div id="stat_balance" class"stat-graph"></div>
-                </div>
+        <div class="row">
+          <div class="col-sm-12 nopadding">
+            <div class="panel-md-margin">
+              <h3>Ma balance</h3>
+              <div id="stat_balance"></div>
             </div>
-	</div><!-- /row -->
-	<div class="row">
-            <div class="col-sm-12 nopadding">	
-                <div class="panel-md-margin">
-                    <h3>Ma consommation</h3>
-                    <div id="stat_last" class"stat-graph"></div>
-                </div>
+          </div>
+        </div><!-- /row -->
+        <div class="row">
+          <div class="col-sm-12 nopadding">
+            <div class="panel-md-margin">
+              <h3>Ma consommation</h3>
+              <div id="stat_last"></div>
             </div>
-	</div><!-- /row -->
+          </div>
+        </div><!-- /row -->
       </div>
       {% endif %}
       <div class="content-right-block">
diff --git a/kfet/templates/kfet/account_read_title.html b/kfet/templates/kfet/account_read_title.html
deleted file mode 100644
index 6712ed77..00000000
--- a/kfet/templates/kfet/account_read_title.html
+++ /dev/null
@@ -1,5 +0,0 @@
-{% if account.user == request.user %}
-    Mon compte
-{% else %}
-    Informations du compte {{ account.trigramme }}
-{% endif %}
diff --git a/kfet/templates/kfet/article_read.html b/kfet/templates/kfet/article_read.html
index 35b484a5..6fe025f6 100644
--- a/kfet/templates/kfet/article_read.html
+++ b/kfet/templates/kfet/article_read.html
@@ -1,6 +1,11 @@
 {% extends 'kfet/base.html' %}
 {% load staticfiles %}
 
+{% block extra_head %}
+<script type="text/javascript" src="{% static 'kfet/js/Chart.bundle.js' %}"></script>
+<script type="text/javascript" src="{% static 'kfet/js/statistic.js' %}"></script>
+{% endblock %}
+
 {% block title %}Informations sur l'article {{ article }}{% endblock %}
 {% block content-header-title %}Article - {{ article.name }}{% endblock %}
 
@@ -82,27 +87,26 @@
       </div>
       <div class="content-right-block content-right-block-transparent">
         <h2>Statistiques</h2>
-	<div class="row">
-            <div class="col-sm-12 nopadding">	
-                <div class="panel-md-margin">
-                    <h3>Ventes de {{ article.name }}</h3>
-                    <div id="stat_last"></div>
-                </div>
+        <div class="row">
+          <div class="col-sm-12 nopadding">
+            <div class="panel-md-margin">
+              <h3>Ventes de {{ article.name }}</h3>
+              <div id="stat_last"></div>
             </div>
-	</div><!-- /row -->
+          </div>
+        </div><!-- /row -->
       </div>
     </div>
   </div>
 </div>
-{% endblock %}
 
-{% block extra_head %}
-<script type="text/javascript" src="{% static 'kfet/js/Chart.bundle.js' %}"></script>
-<script type="text/javascript" src="{% static 'kfet/js/statistic.js' %}"></script>
-<script>
-jQuery(document).ready(function() {
-    var stat_last = new StatsGroup("{% url 'kfet.article.stat.last' article.id %}",
-                                    $("#stat_last"));
+<script type="text/javascript">
+$(document).ready(function() {
+    var stat_last = new StatsGroup(
+        "{% url 'kfet.article.stat.sales.list' article.id %}",
+        $("#stat_last"),
+    );
 });
 </script>
+
 {% endblock %}
diff --git a/kfet/tests.py b/kfet/tests.py
index 5bea7afa..991b2545 100644
--- a/kfet/tests.py
+++ b/kfet/tests.py
@@ -1,5 +1,70 @@
 # -*- coding: utf-8 -*-
 
-from django.test import TestCase
+from unittest.mock import patch
 
-# Écrire les tests ici
+from django.test import TestCase, Client
+from django.contrib.auth.models import User, Permission
+
+from .models import Account, Article, ArticleCategory
+
+
+class TestStats(TestCase):
+    @patch('kfet.signals.messages')
+    def test_user_stats(self, mock_messages):
+        """
+        Checks that we can get the stat-related pages without any problem.
+        """
+        # We setup two users and an article. Only the first user is part of the
+        # team.
+        user = User.objects.create(username="Foobar")
+        user.set_password("foobar")
+        user.save()
+        Account.objects.create(trigramme="FOO", cofprofile=user.profile)
+        perm = Permission.objects.get(codename="is_team")
+        user.user_permissions.add(perm)
+
+        user2 = User.objects.create(username="Barfoo")
+        user2.set_password("barfoo")
+        user2.save()
+        Account.objects.create(trigramme="BAR", cofprofile=user2.profile)
+
+        article = Article.objects.create(
+            name="article",
+            category=ArticleCategory.objects.create(name="C")
+        )
+
+        # Each user have its own client
+        client = Client()
+        client.login(username="Foobar", password="foobar")
+        client2 = Client()
+        client2.login(username="Barfoo", password="barfoo")
+
+        # 1. FOO should be able to get these pages but BAR receives a Forbidden
+        # response
+        user_urls = [
+            "/k-fet/accounts/FOO/stat/operations/list",
+            "/k-fet/accounts/FOO/stat/operations?{}".format(
+                '&'.join(["scale=day",
+                          "types=['purchase']",
+                          "scale_args={'n_steps':+7,+'last':+True}",
+                          "format=json"])),
+            "/k-fet/accounts/FOO/stat/balance/list",
+            "/k-fet/accounts/FOO/stat/balance?format=json"
+        ]
+        for url in user_urls:
+            resp = client.get(url)
+            self.assertEqual(200, resp.status_code)
+            resp2 = client2.get(url)
+            self.assertEqual(403, resp2.status_code)
+
+        # 2. FOO is a member of the team and can get these pages but BAR
+        # receives a Redirect response
+        articles_urls = [
+            "/k-fet/articles/{}/stat/sales/list".format(article.pk),
+            "/k-fet/articles/{}/stat/sales".format(article.pk)
+        ]
+        for url in articles_urls:
+            resp = client.get(url)
+            self.assertEqual(200, resp.status_code)
+            resp2 = client2.get(url, follow=True)
+            self.assertRedirects(resp2, "/")
diff --git a/kfet/urls.py b/kfet/urls.py
index 94a9eaec..0ffeb84f 100644
--- a/kfet/urls.py
+++ b/kfet/urls.py
@@ -69,28 +69,19 @@ urlpatterns = [
         name='kfet.account.negative'),
 
     # Account - Statistics
-    url('^accounts/(?P<trigramme>.{3})/stat/last/$',
-        views.AccountStatLastAll.as_view(),
-        name = 'kfet.account.stat.last'),
-    url('^accounts/(?P<trigramme>.{3})/stat/last/month/$',
-        views.AccountStatLastMonth.as_view(),
-        name = 'kfet.account.stat.last.month'),
-    url('^accounts/(?P<trigramme>.{3})/stat/last/week/$',
-        views.AccountStatLastWeek.as_view(),
-        name = 'kfet.account.stat.last.week'),
-    url('^accounts/(?P<trigramme>.{3})/stat/last/day/$',
-        views.AccountStatLastDay.as_view(),
-        name = 'kfet.account.stat.last.day'),
+    url('^accounts/(?P<trigramme>.{3})/stat/operations/list$',
+        views.AccountStatOperationList.as_view(),
+        name='kfet.account.stat.operation.list'),
+    url('^accounts/(?P<trigramme>.{3})/stat/operations$',
+        views.AccountStatOperation.as_view(),
+        name='kfet.account.stat.operation'),
 
-    url('^accounts/(?P<trigramme>.{3})/stat/balance/$',
-        views.AccountStatBalanceAll.as_view(),
-        name = 'kfet.account.stat.balance'),
-    url('^accounts/(?P<trigramme>.{3})/stat/balance/d/(?P<nb_date>\d*)/$',
+    url(r'^accounts/(?P<trigramme>.{3})/stat/balance/list$',
+        views.AccountStatBalanceList.as_view(),
+        name='kfet.account.stat.balance.list'),
+    url(r'^accounts/(?P<trigramme>.{3})/stat/balance$',
         views.AccountStatBalance.as_view(),
-        name = 'kfet.account.stat.balance.days'),
-    url('^accounts/(?P<trigramme>.{3})/stat/balance/anytime/$',
-        views.AccountStatBalance.as_view(),
-        name = 'kfet.account.stat.balance.anytime'),
+        name='kfet.account.stat.balance'),
 
     # -----
     # Checkout urls
@@ -149,20 +140,14 @@ urlpatterns = [
     # Article - Update
     url('^articles/(?P<pk>\d+)/edit$',
         teamkfet_required(views.ArticleUpdate.as_view()),
-        name = 'kfet.article.update'),
+        name='kfet.article.update'),
     # Article - Statistics
-    url('^articles/(?P<pk>\d+)/stat/last/$',
-        views.ArticleStatLastAll.as_view(),
-        name = 'kfet.article.stat.last'),
-    url('^articles/(?P<pk>\d+)/stat/last/month/$',
-        views.ArticleStatLastMonth.as_view(),
-        name = 'kfet.article.stat.last.month'),
-    url('^articles/(?P<pk>\d+)/stat/last/week/$',
-        views.ArticleStatLastWeek.as_view(),
-        name = 'kfet.article.stat.last.week'),
-    url('^articles/(?P<pk>\d+)/stat/last/day/$',
-        views.ArticleStatLastDay.as_view(),
-        name = 'kfet.article.stat.last.day'),
+    url(r'^articles/(?P<pk>\d+)/stat/sales/list$',
+        views.ArticleStatSalesList.as_view(),
+        name='kfet.article.stat.sales.list'),
+    url(r'^articles/(?P<pk>\d+)/stat/sales$',
+        views.ArticleStatSales.as_view(),
+        name='kfet.article.stat.sales'),
 
     # -----
     # K-Psul urls
diff --git a/kfet/views.py b/kfet/views.py
index 78c65002..524b35ba 100644
--- a/kfet/views.py
+++ b/kfet/views.py
@@ -1,12 +1,14 @@
 # -*- coding: utf-8 -*-
 
+import ast
+from urllib.parse import urlencode
+
 from django.shortcuts import render, get_object_or_404, redirect
 from django.core.exceptions import PermissionDenied
 from django.core.cache import cache
 from django.views.generic import ListView, DetailView, TemplateView
-from django.views.generic.list import BaseListView, MultipleObjectTemplateResponseMixin
-from django.views.generic.detail import BaseDetailView, SingleObjectTemplateResponseMixin
-from django.views.generic.edit import CreateView, UpdateView, DeleteView, FormView
+from django.views.generic.detail import BaseDetailView
+from django.views.generic.edit import CreateView, UpdateView
 from django.core.urlresolvers import reverse, reverse_lazy
 from django.contrib import messages
 from django.contrib.messages.views import SuccessMessageMixin
@@ -46,10 +48,8 @@ from decimal import Decimal
 import django_cas_ng
 import heapq
 import statistics
-from .statistic import daynames, monthnames, weeknames, \
-        lastdays, lastweeks, lastmonths, \
-        this_morning, this_monday_morning, this_first_month_day, \
-        tot_ventes
+from kfet.statistic import ScaleMixin, last_stats_manifest, tot_ventes
+
 
 class Home(TemplateView):
     template_name   = "kfet/home.html"
@@ -2029,87 +2029,54 @@ class JSONResponseMixin(object):
         return context
 
 
-class JSONDetailView(JSONResponseMixin,
-                     BaseDetailView):
-    """
-    Returns a DetailView that renders a JSON
-    """
+class JSONDetailView(JSONResponseMixin, BaseDetailView):
+    """Returns a DetailView that renders a JSON."""
+
     def render_to_response(self, context):
         return self.render_to_json_response(context)
 
-class HybridDetailView(JSONResponseMixin,
-                       SingleObjectTemplateResponseMixin,
-                       BaseDetailView):
-    """
-    Returns a DetailView as an html page except if a JSON file is requested
-    by the GET method in which case it returns a JSON response.
-    """
-    def render_to_response(self, context):
-        # Look for a 'format=json' GET argument
-        if self.request.GET.get('format') == 'json':
-            return self.render_to_json_response(context)
-        else:
-            return super(HybridDetailView, self).render_to_response(context)
+
+class PkUrlMixin(object):
+
+    def get_object(self, *args, **kwargs):
+        get_by = self.kwargs.get(self.pk_url_kwarg)
+        return get_object_or_404(self.model, **{self.pk_url_kwarg: get_by})
 
 
-class HybridListView(JSONResponseMixin,
-                     MultipleObjectTemplateResponseMixin,
-                     BaseListView):
-    """
-    Returns a ListView as an html page except if a JSON file is requested
-    by the GET method in which case it returns a JSON response.
-    """
-    def render_to_response(self, context):
-        # Look for a 'format=json' GET argument
-        if self.request.GET.get('format') == 'json':
-            return self.render_to_json_response(context)
-        else:
-            return super(HybridListView, self).render_to_response(context)
+class SingleResumeStat(JSONDetailView):
+    """Manifest for a kind of a stat about an object.
 
+    Returns JSON whose payload is an array containing descriptions of a stat:
+    url to retrieve data, label, ...
 
-class ObjectResumeStat(JSONDetailView):
     """
-    Summarize all the stats of an object
-    Handles JSONResponse
-    """
-    context_object_name = ''
     id_prefix = ''
-    # nombre de vues à résumer
-    nb_stat = 2
-    # Le combienième est celui par defaut ?
-    # (entre 0 et nb_stat-1)
     nb_default = 0
-    stat_labels = ['stat_1', 'stat_2']
-    stat_urls = ['url_1', 'url_2']
 
-    # sert à renverser les urls
-    # utile de le surcharger quand l'url prend d'autres arguments que l'id
-    def get_object_url_kwargs(self, **kwargs):
-        return {'pk': self.object.id}
-
-    def url_kwargs(self, **kwargs):
-        return [{}] * self.nb_stat
+    stats = []
+    url_stat = None
 
     def get_context_data(self, **kwargs):
         # On n'hérite pas
         object_id = self.object.id
-        url_kwargs = self.url_kwargs()
         context = {}
-        stats = {}
-        for i in range(self.nb_stat):
-            stats[i] = {
-                'label': self.stat_labels[i],
-                'btn': "btn_%s_%d_%d" % (self.id_prefix,
-                                         object_id,
-                                         i),
-                'url': reverse(self.stat_urls[i],
-                                    kwargs=dict(
-                                        self.get_object_url_kwargs(),
-                                        **url_kwargs[i]
-                                        ),
-                                    ),
-                }
-        prefix = "%s_%d" % (self.id_prefix, object_id)
+        stats = []
+        prefix = '{}_{}'.format(self.id_prefix, object_id)
+        for i, stat_def in enumerate(self.stats):
+            url_pk = getattr(self.object, self.pk_url_kwarg)
+            url_params_d = stat_def.get('url_params', {})
+            if len(url_params_d) > 0:
+                url_params = '?{}'.format(urlencode(url_params_d))
+            else:
+                url_params = ''
+            stats.append({
+                'label': stat_def['label'],
+                'btn': 'btn_{}_{}'.format(prefix, i),
+                'url': '{url}{params}'.format(
+                    url=reverse(self.url_stat, args=[url_pk]),
+                    params=url_params,
+                ),
+            })
         context['id_prefix'] = prefix
         context['content_id'] = "content_%s" % prefix
         context['stats'] = stats
@@ -2124,87 +2091,84 @@ class ObjectResumeStat(JSONDetailView):
 ID_PREFIX_ACC_BALANCE = "balance_acc"
 
 
-# Un résumé de toutes les vues ArticleStatBalance
-# REND DU JSON
-class AccountStatBalanceAll(ObjectResumeStat):
+class AccountStatBalanceList(PkUrlMixin, SingleResumeStat):
+    """Manifest for balance stats of an account."""
     model = Account
     context_object_name = 'account'
-    trigramme_url_kwarg = 'trigramme'
+    pk_url_kwarg = 'trigramme'
+    url_stat = 'kfet.account.stat.balance'
     id_prefix = ID_PREFIX_ACC_BALANCE
-    nb_stat = 5
+    stats = [
+        {
+            'label': 'Tout le temps',
+        },
+        {
+            'label': '1 an',
+            'url_params': {'last_days': 365},
+        },
+        {
+            'label': '6 mois',
+            'url_params': {'last_days': 183},
+        },
+        {
+            'label': '3 mois',
+            'url_params': {'last_days': 90},
+        },
+        {
+            'label': '30 jours',
+            'url_params': {'last_days': 30},
+        },
+    ]
     nb_default = 0
-    stat_labels = ["Tout le temps", "1 an", "6 mois", "3 mois", "30 jours"]
-    stat_urls = ['kfet.account.stat.balance.anytime'] \
-        + ['kfet.account.stat.balance.days'] * 4
 
-    def get_object(self, **kwargs):
-        trigramme = self.kwargs.get(self.trigramme_url_kwarg)
-        return get_object_or_404(Account, trigramme=trigramme)
-
-    def get_object_url_kwargs(self, **kwargs):
-        return {'trigramme': self.object.trigramme}
-
-    def url_kwargs(self, **kwargs):
-        context_list = (super(AccountStatBalanceAll, self)
-                        .url_kwargs(**kwargs))
-        context_list[1] = {'nb_date': 365}
-        context_list[2] = {'nb_date': 183}
-        context_list[3] = {'nb_date': 90}
-        context_list[4] = {'nb_date': 30}
-        return context_list
+    def get_object(self, *args, **kwargs):
+        obj = super().get_object(*args, **kwargs)
+        if self.request.user != obj.user:
+            raise PermissionDenied
+        return obj
 
     @method_decorator(login_required)
     def dispatch(self, *args, **kwargs):
-        return super(AccountStatBalanceAll, self).dispatch(*args, **kwargs)
+        return super().dispatch(*args, **kwargs)
 
 
-class AccountStatBalance(JSONDetailView):
-    """
-    Returns a JSON containing the evolution a the personnal
-    balance of a trigramme between timezone.now() and `nb_days`
-    ago (specified to the view as an argument)
-    takes into account the Operations and the Transfers
-    does not takes into account the balance offset
+class AccountStatBalance(PkUrlMixin, JSONDetailView):
+    """Datasets of balance of an account.
+
+    Operations and Transfers are taken into account.
+
     """
     model = Account
-    trigramme_url_kwarg = 'trigramme'
-    nb_date_url_kwargs = 'nb_date'
+    pk_url_kwarg = 'trigramme'
     context_object_name = 'account'
-    id_prefix = ""
 
-    def get_object(self, **kwargs):
-        trigramme = self.kwargs.get(self.trigramme_url_kwarg)
-        return get_object_or_404(Account, trigramme=trigramme)
-
-    def get_changes_list(self, **kwargs):
+    def get_changes_list(self, last_days=None, begin_date=None, end_date=None):
         account = self.object
-        nb_date = self.kwargs.get(self.nb_date_url_kwargs, None)
-        end_date = this_morning()
-        if nb_date is None:
-            begin_date = timezone.datetime(year=1980, month=1, day=1)
-            anytime = True
-        else:
-            begin_date = this_morning() \
-                    - timezone.timedelta(days=int(nb_date))
-            anytime = False
-        # On récupère les opérations
+
+        # prepare filters
+        if last_days is not None:
+            end_date = timezone.now()
+            begin_date = end_date - timezone.timedelta(days=last_days)
+
+        # prepare querysets
         # TODO: retirer les opgroup dont tous les op sont annulées
-        opgroups = list(OperationGroup.objects
-                        .filter(on_acc=account)
-                        .filter(at__gte=begin_date)
-                        .filter(at__lte=end_date))
-        # On récupère les transferts reçus
-        received_transfers = list(Transfer.objects
-                                  .filter(to_acc=account)
-                                  .filter(canceled_at=None)
-                                  .filter(group__at__gte=begin_date)
-                                  .filter(group__at__lte=end_date))
-        # On récupère les transferts émis
-        emitted_transfers = list(Transfer.objects
-                                 .filter(from_acc=account)
-                                 .filter(canceled_at=None)
-                                 .filter(group__at__gte=begin_date)
-                                 .filter(group__at__lte=end_date))
+        opegroups = OperationGroup.objects.filter(on_acc=account)
+        recv_transfers = Transfer.objects.filter(to_acc=account,
+                                                 canceled_at=None)
+        sent_transfers = Transfer.objects.filter(from_acc=account,
+                                                 canceled_at=None)
+
+        # apply filters
+        if begin_date is not None:
+            opegroups = opegroups.filter(at__gte=begin_date)
+            recv_transfers = recv_transfers.filter(group__at__gte=begin_date)
+            sent_transfers = sent_transfers.filter(group__at__gte=begin_date)
+
+        if end_date is not None:
+            opegroups = opegroups.filter(at__lte=end_date)
+            recv_transfers = recv_transfers.filter(group__at__lte=end_date)
+            sent_transfers = sent_transfers.filter(group__at__lte=end_date)
+
         # On transforme tout ça en une liste de dictionnaires sous la forme
         # {'at': date,
         #  'amount': changement de la balance (négatif si diminue la balance,
@@ -2214,76 +2178,86 @@ class AccountStatBalance(JSONDetailView):
         #                                      sera mis à jour lors d'une
         #                                      autre passe)
         # }
-        actions = [
-            # Maintenant (à changer si on gère autre chose que now)
+
+        actions = []
+
+        actions.append({
+            'at': (begin_date or account.created_at).isoformat(),
+            'amount': 0,
+            'label': 'début',
+            'balance': 0,
+        })
+        actions.append({
+            'at': (end_date or timezone.now()).isoformat(),
+            'amount': 0,
+            'label': 'fin',
+            'balance': 0,
+        })
+
+        actions += [
             {
-                'at': end_date.isoformat(),
-                'amout': 0,
-                'label': "actuel",
+                'at': ope_grp.at.isoformat(),
+                'amount': ope_grp.amount,
+                'label': str(ope_grp),
                 'balance': 0,
-            }
-        ] + [
-            {
-                'at': op.at.isoformat(),
-                'amount': op.amount,
-                'label': str(op),
-                'balance': 0,
-            } for op in opgroups
+            } for ope_grp in opegroups
         ] + [
             {
                 'at': tr.group.at.isoformat(),
                 'amount': tr.amount,
-                'label': "%d€: %s -> %s" % (tr.amount,
-                                            tr.from_acc.trigramme,
-                                            tr.to_acc.trigramme),
+                'label': str(tr),
                 'balance': 0,
-            } for tr in received_transfers
+            } for tr in recv_transfers
         ] + [
             {
                 'at': tr.group.at.isoformat(),
                 'amount': -tr.amount,
-                'label': "%d€: %s -> %s" % (tr.amount,
-                                            tr.from_acc.trigramme,
-                                            tr.to_acc.trigramme),
+                'label': str(tr),
                 'balance': 0,
-            } for tr in emitted_transfers
+            } for tr in sent_transfers
         ]
-        if not anytime:
-            actions += [
-                # Date de début :
-                {
-                    'at': begin_date.isoformat(),
-                    'amount': 0,
-                    'label': "début",
-                    'balance': 0,
-                }
-            ]
         # Maintenant on trie la liste des actions par ordre du plus récent
         # an plus ancien et on met à jour la balance
-        actions = sorted(actions, key=lambda k: k['at'], reverse=True)
-        actions[0]['balance'] = account.balance
-        for i in range(len(actions)-1):
-            actions[i+1]['balance'] = actions[i]['balance'] \
-                    - actions[i+1]['amount']
+        if len(actions) > 1:
+            actions = sorted(actions, key=lambda k: k['at'], reverse=True)
+            actions[0]['balance'] = account.balance
+            for i in range(len(actions)-1):
+                actions[i+1]['balance'] = \
+                        actions[i]['balance'] - actions[i+1]['amount']
         return actions
 
-    def get_context_data(self, **kwargs):
+    def get_context_data(self, *args, **kwargs):
         context = {}
-        changes = self.get_changes_list()
-        nb_days = self.kwargs.get(self.nb_date_url_kwargs, None)
-        if nb_days is None:
-            nb_days_string = 'anytime'
-        else:
-            nb_days_string = str(int(nb_days))
-        context['charts'] = [ { "color": "rgb(255, 99, 132)",
-                                "label": "Balance",
-                                "values": changes } ]
+
+        last_days = self.request.GET.get('last_days', None)
+        if last_days is not None:
+            last_days = int(last_days)
+        begin_date = self.request.GET.get('begin_date', None)
+        end_date = self.request.GET.get('end_date', None)
+
+        changes = self.get_changes_list(
+            last_days=last_days,
+            begin_date=begin_date, end_date=end_date,
+        )
+
+        context['charts'] = [{
+            "color": "rgb(255, 99, 132)",
+            "label": "Balance",
+            "values": changes,
+        }]
         context['is_time_chart'] = True
-        context['min_date'] = changes[len(changes)-1]['at']
-        context['max_date'] = changes[0]['at']
+        if len(changes) > 0:
+            context['min_date'] = changes[-1]['at']
+            context['max_date'] = changes[0]['at']
         # TODO: offset
         return context
 
+    def get_object(self, *args, **kwargs):
+        obj = super().get_object(*args, **kwargs)
+        if self.request.user != obj.user:
+            raise PermissionDenied
+        return obj
+
     @method_decorator(login_required)
     def dispatch(self, *args, **kwargs):
         return super(AccountStatBalance, self).dispatch(*args, **kwargs)
@@ -2298,140 +2272,77 @@ ID_PREFIX_ACC_LAST_WEEKS = "last_weeks_acc"
 ID_PREFIX_ACC_LAST_MONTHS = "last_months_acc"
 
 
-# Un résumé de toutes les vues ArticleStatLast
-# NE REND PAS DE JSON
-class AccountStatLastAll(ObjectResumeStat):
+class AccountStatOperationList(PkUrlMixin, SingleResumeStat):
+    """Manifest for operations stats of an account."""
     model = Account
     context_object_name = 'account'
-    trigramme_url_kwarg = 'trigramme'
+    pk_url_kwarg = 'trigramme'
     id_prefix = ID_PREFIX_ACC_LAST
-    nb_stat = 3
     nb_default = 2
-    stat_labels = ["Derniers mois", "Dernières semaines", "Derniers jours"]
-    stat_urls = ['kfet.account.stat.last.month',
-                 'kfet.account.stat.last.week',
-                 'kfet.account.stat.last.day']
+    stats = last_stats_manifest(types=[Operation.PURCHASE])
+    url_stat = 'kfet.account.stat.operation'
 
-    def get_object(self, **kwargs):
-        trigramme = self.kwargs.get(self.trigramme_url_kwarg)
-        return get_object_or_404(Account, trigramme=trigramme)
-
-    def get_object_url_kwargs(self, **kwargs):
-        return {'trigramme': self.object.trigramme}
+    def get_object(self, *args, **kwargs):
+        obj = super().get_object(*args, **kwargs)
+        if self.request.user != obj.user:
+            raise PermissionDenied
+        return obj
 
     @method_decorator(login_required)
     def dispatch(self, *args, **kwargs):
-        return super(AccountStatLastAll, self).dispatch(*args, **kwargs)
+        return super().dispatch(*args, **kwargs)
 
 
-class AccountStatLast(JSONDetailView):
-    """
-    Returns a JSON containing the evolution a the personnal
-    consommation of a trigramme at the diffent dates specified
-    """
+class AccountStatOperation(ScaleMixin, PkUrlMixin, JSONDetailView):
+    """Datasets of operations of an account."""
     model = Account
-    trigramme_url_kwarg = 'trigramme'
+    pk_url_kwarg = 'trigramme'
     context_object_name = 'account'
-    end_date = timezone.now()
     id_prefix = ""
 
-    # doit rendre un dictionnaire des dates
-    # la première date correspond au début
-    # la dernière date est la fin de la dernière plage
-    def get_dates(self, **kwargs):
-        return {}
-
-    # doit rendre un dictionnaire des labels
-    # le dernier label ne sera pas utilisé
-    def get_labels(self, **kwargs):
-        pass
-
-    def get_object(self, **kwargs):
-        trigramme = self.kwargs.get(self.trigramme_url_kwarg)
-        return get_object_or_404(Account, trigramme=trigramme)
-
-    def sort_operations(self, **kwargs):
-        # On récupère les dates
-        dates = self.get_dates()
-        # On ajoute la date de fin
-        extended_dates = dates.copy()
-        extended_dates[len(dates)+1] = self.end_date
+    def get_operations(self, scale, types=None):
         # On selectionne les opérations qui correspondent
         # à l'article en question et qui ne sont pas annulées
         # puis on choisi pour chaques intervalle les opérations
         # effectuées dans ces intervalles de temps
         all_operations = (Operation.objects
-                          .filter(type='purchase')
                           .filter(group__on_acc=self.object)
                           .filter(canceled_at=None)
                           )
-        operations = {}
-        for i in dates:
-            operations[i] = (all_operations
-                             .filter(group__at__gte=extended_dates[i])
-                             .filter(group__at__lte=extended_dates[i+1])
-                             )
-        return operations
+        if types is not None:
+            all_operations = all_operations.filter(type__in=types)
+        chunks = self.chunkify_qs(all_operations, scale, field='group__at')
+        return chunks
 
-    def get_context_data(self, **kwargs):
-        context = {}
-        nb_ventes = {}
-        # On récupère les labels des dates
-        context['labels'] = self.get_labels().copy()
+    def get_context_data(self, *args, **kwargs):
+        old_ctx = super().get_context_data(*args, **kwargs)
+        context = {'labels': old_ctx['labels']}
+        scale = self.scale
+
+        types = self.request.GET.get('types', None)
+        if types is not None:
+            types = ast.literal_eval(types)
+
+        operations = self.get_operations(types=types, scale=scale)
         # On compte les opérations
-        operations = self.sort_operations()
-        for i in operations:
-            nb_ventes[i] = tot_ventes(operations[i])
-        context['charts'] = [ { "color": "rgb(255, 99, 132)",
-                                "label": "NB items achetés",
-                                "values": nb_ventes } ]
+        nb_ventes = []
+        for chunk in operations:
+            nb_ventes.append(tot_ventes(chunk))
+
+        context['charts'] = [{"color": "rgb(255, 99, 132)",
+                              "label": "NB items achetés",
+                              "values": nb_ventes}]
         return context
 
+    def get_object(self, *args, **kwargs):
+        obj = super().get_object(*args, **kwargs)
+        if self.request.user != obj.user:
+            raise PermissionDenied
+        return obj
+
     @method_decorator(login_required)
     def dispatch(self, *args, **kwargs):
-        return super(AccountStatLast, self).dispatch(*args, **kwargs)
-
-
-# Rend les achats pour ce compte des 7 derniers jours
-# Aujourd'hui non compris
-class AccountStatLastDay(AccountStatLast):
-    end_date = this_morning()
-    id_prefix = ID_PREFIX_ACC_LAST_DAYS
-
-    def get_dates(self, **kwargs):
-        return lastdays(7)
-
-    def get_labels(self, **kwargs):
-        days = lastdays(7)
-        return daynames(days)
-
-
-# Rend les achats de ce compte des 7 dernières semaines
-# La semaine en cours n'est pas comprise
-class AccountStatLastWeek(AccountStatLast):
-    end_date = this_monday_morning()
-    id_prefix = ID_PREFIX_ACC_LAST_WEEKS
-
-    def get_dates(self, **kwargs):
-        return lastweeks(7)
-
-    def get_labels(self, **kwargs):
-        weeks = lastweeks(7)
-        return weeknames(weeks)
-
-
-# Rend les achats de ce compte des 7 derniers mois
-# Le mois en cours n'est pas compris
-class AccountStatLastMonth(AccountStatLast):
-    end_date = this_monday_morning()
-    id_prefix = ID_PREFIX_ACC_LAST_MONTHS
-
-    def get_dates(self, **kwargs):
-        return lastmonths(7)
-
-    def get_labels(self, **kwargs):
-        months = lastmonths(7)
-        return monthnames(months)
+        return super().dispatch(*args, **kwargs)
 
 
 # ------------------------
@@ -2443,143 +2354,64 @@ ID_PREFIX_ART_LAST_WEEKS = "last_weeks_art"
 ID_PREFIX_ART_LAST_MONTHS = "last_months_art"
 
 
-# Un résumé de toutes les vues ArticleStatLast
-# NE REND PAS DE JSON
-class ArticleStatLastAll(ObjectResumeStat):
+class ArticleStatSalesList(SingleResumeStat):
+    """Manifest for sales stats of an article."""
     model = Article
     context_object_name = 'article'
     id_prefix = ID_PREFIX_ART_LAST
-    nb_stat = 3
     nb_default = 2
-    stat_labels = ["Derniers mois", "Dernières semaines", "Derniers jours"]
-    stat_urls = ['kfet.article.stat.last.month',
-                 'kfet.article.stat.last.week',
-                 'kfet.article.stat.last.day']
+    url_stat = 'kfet.article.stat.sales'
+    stats = last_stats_manifest()
 
-    @method_decorator(login_required)
+    @method_decorator(teamkfet_required)
     def dispatch(self, *args, **kwargs):
-        return super(ArticleStatLastAll, self).dispatch(*args, **kwargs)
+        return super().dispatch(*args, **kwargs)
 
 
-class ArticleStatLast(JSONDetailView):
-    """
-    Returns a JSON containing the consommation
-    of an article at the diffent dates precised
-    """
+class ArticleStatSales(ScaleMixin, JSONDetailView):
+    """Datasets of sales of an article."""
     model = Article
     context_object_name = 'article'
-    end_date = timezone.now()
-    id_prefix = ""
 
-    def render_to_response(self, context):
-        # Look for a 'format=json' GET argument
-        if self.request.GET.get('format') == 'json':
-            return self.render_to_json_response(context)
-        else:
-            return super(ArticleStatLast, self).render_to_response(context)
+    def get_context_data(self, *args, **kwargs):
+        old_ctx = super().get_context_data(*args, **kwargs)
+        context = {'labels': old_ctx['labels']}
+        scale = self.scale
 
-    # doit rendre un dictionnaire des dates
-    # la première date correspond au début
-    # la dernière date est la fin de la dernière plage
-    def get_dates(self, **kwargs):
-        pass
-
-    # doit rendre un dictionnaire des labels
-    # le dernier label ne sera pas utilisé
-    def get_labels(self, **kwargs):
-        pass
-
-    def get_context_data(self, **kwargs):
-        context = {}
-        # On récupère les labels des dates
-        context['labels'] = self.get_labels().copy()
-        # On récupère les dates
-        dates = self.get_dates()
-        # On ajoute la date de fin
-        extended_dates = dates.copy()
-        extended_dates[len(dates)+1] = self.end_date
         # On selectionne les opérations qui correspondent
         # à l'article en question et qui ne sont pas annulées
         # puis on choisi pour chaques intervalle les opérations
         # effectuées dans ces intervalles de temps
-        all_operations = (Operation.objects
-                          .filter(type='purchase')
-                          .filter(article=self.object)
-                          .filter(canceled_at=None)
-                          )
-        operations = {}
-        for i in dates:
-            operations[i] = (all_operations
-                             .filter(group__at__gte=extended_dates[i])
-                             .filter(group__at__lte=extended_dates[i+1])
-                             )
+        all_operations = (
+            Operation.objects
+            .filter(type=Operation.PURCHASE,
+                    article=self.object,
+                    canceled_at=None,
+                    )
+        )
+        chunks = self.chunkify_qs(all_operations, scale, field='group__at')
         # On compte les opérations
-        nb_ventes = {}
-        nb_accounts = {}
-        nb_liq = {}
-        for i in operations:
-            nb_ventes[i] = tot_ventes(operations[i])
-            nb_liq[i] = tot_ventes(
-                        operations[i]
-                        .filter(group__on_acc__trigramme='LIQ')
-                        )
-            nb_accounts[i] = tot_ventes(
-                        operations[i]
-                        .exclude(group__on_acc__trigramme='LIQ')
-                        )
-        context['charts'] = [ { "color": "rgb(255, 99, 132)",
-                                "label": "Toutes consommations",
-                                "values": nb_ventes },
-                              { "color": "rgb(54, 162, 235)",
-                                "label": "LIQ",
-                                "values": nb_liq },
-                              { "color": "rgb(255, 205, 86)",
-                                "label": "Comptes K-Fêt",
-                                "values": nb_accounts } ]
+        nb_ventes = []
+        nb_accounts = []
+        nb_liq = []
+        for qs in chunks:
+            nb_ventes.append(
+                tot_ventes(qs))
+            nb_liq.append(
+                tot_ventes(qs.filter(group__on_acc__trigramme='LIQ')))
+            nb_accounts.append(
+                tot_ventes(qs.exclude(group__on_acc__trigramme='LIQ')))
+        context['charts'] = [{"color": "rgb(255, 99, 132)",
+                              "label": "Toutes consommations",
+                              "values": nb_ventes},
+                             {"color": "rgb(54, 162, 235)",
+                              "label": "LIQ",
+                              "values": nb_liq},
+                             {"color": "rgb(255, 205, 86)",
+                              "label": "Comptes K-Fêt",
+                              "values": nb_accounts}]
         return context
 
-    @method_decorator(login_required)
+    @method_decorator(teamkfet_required)
     def dispatch(self, *args, **kwargs):
-        return super(ArticleStatLast, self).dispatch(*args, **kwargs)
-
-
-# Rend les ventes des 7 derniers jours
-# Aujourd'hui non compris
-class ArticleStatLastDay(ArticleStatLast):
-    end_date = this_morning()
-    id_prefix = ID_PREFIX_ART_LAST_DAYS
-
-    def get_dates(self, **kwargs):
-        return lastdays(7)
-
-    def get_labels(self, **kwargs):
-        days = lastdays(7)
-        return daynames(days)
-
-
-# Rend les ventes de 7 dernières semaines
-# La semaine en cours n'est pas comprise
-class ArticleStatLastWeek(ArticleStatLast):
-    end_date = this_monday_morning()
-    id_prefix = ID_PREFIX_ART_LAST_WEEKS
-
-    def get_dates(self, **kwargs):
-        return lastweeks(7)
-
-    def get_labels(self, **kwargs):
-        weeks = lastweeks(7)
-        return weeknames(weeks)
-
-
-# Rend les ventes des 7 derniers mois
-# Le mois en cours n'est pas compris
-class ArticleStatLastMonth(ArticleStatLast):
-    end_date = this_monday_morning()
-    id_prefix = ID_PREFIX_ART_LAST_MONTHS
-
-    def get_dates(self, **kwargs):
-        return lastmonths(7)
-
-    def get_labels(self, **kwargs):
-        months = lastmonths(7)
-        return monthnames(months)
+        return super().dispatch(*args, **kwargs)
diff --git a/requirements.txt b/requirements.txt
index 06f6c46e..ce081588 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -20,3 +20,4 @@ django-widget-tweaks==1.4.1
 git+https://git.eleves.ens.fr/cof-geek/django_custommail.git#egg=django_custommail
 ldap3
 git+https://github.com/Aureplop/channels.git#egg=channels
+python-dateutil