diff --git a/app/controllers/experts/avis_controller.rb b/app/controllers/experts/avis_controller.rb
index 78de84947..04114174a 100644
--- a/app/controllers/experts/avis_controller.rb
+++ b/app/controllers/experts/avis_controller.rb
@@ -91,7 +91,7 @@ module Experts
         redirect_to url_for(expert_all_avis_path)
       else
         flash[:alert] = user.errors.full_messages
-        redirect_to url_for(sign_up_expert_avis_path(procedure_id, avis_id, email))
+        redirect_to sign_up_expert_avis_path(procedure_id, avis_id, email: email)
       end
     end
 
diff --git a/app/controllers/instructeurs/procedures_controller.rb b/app/controllers/instructeurs/procedures_controller.rb
index b96c83dc5..bb556675c 100644
--- a/app/controllers/instructeurs/procedures_controller.rb
+++ b/app/controllers/instructeurs/procedures_controller.rb
@@ -210,6 +210,7 @@ module Instructeurs
       @dossiers_funnel = @procedure.stats_dossiers_funnel
       @termines_states = @procedure.stats_termines_states
       @termines_by_week = @procedure.stats_termines_by_week
+      @usual_traitement_time_by_month = @procedure.stats_usual_traitement_time_by_month_in_days
     end
 
     private
diff --git a/app/controllers/users/statistiques_controller.rb b/app/controllers/users/statistiques_controller.rb
index 8b1611027..5ccafc2bf 100644
--- a/app/controllers/users/statistiques_controller.rb
+++ b/app/controllers/users/statistiques_controller.rb
@@ -5,6 +5,7 @@ module Users
       return procedure_not_found if @procedure.blank? || @procedure.brouillon?
 
       @usual_traitement_time = @procedure.stats_usual_traitement_time
+      @usual_traitement_time_by_month = @procedure.stats_usual_traitement_time_by_month_in_days
       @dossiers_funnel = @procedure.stats_dossiers_funnel
       @termines_states = @procedure.stats_termines_states
       @termines_by_week = @procedure.stats_termines_by_week
diff --git a/app/models/concerns/procedure_stats_concern.rb b/app/models/concerns/procedure_stats_concern.rb
index 6c8414e8c..cbe89c5a8 100644
--- a/app/models/concerns/procedure_stats_concern.rb
+++ b/app/models/concerns/procedure_stats_concern.rb
@@ -1,9 +1,21 @@
 module ProcedureStatsConcern
   extend ActiveSupport::Concern
 
+  NB_DAYS_RECENT_DOSSIERS = 30
+  # Percentage of dossiers considered to compute the 'usual traitement time'.
+  # For instance, a value of '90' means that the usual traitement time will return
+  # the duration under which 90% of the given dossiers are closed.
+  USUAL_TRAITEMENT_TIME_PERCENTILE = 90
+
   def stats_usual_traitement_time
     Rails.cache.fetch("#{cache_key_with_version}/stats_usual_traitement_time", expires_in: 12.hours) do
-      usual_traitement_time
+      usual_traitement_time_for_recent_dossiers(NB_DAYS_RECENT_DOSSIERS)
+    end
+  end
+
+  def stats_usual_traitement_time_by_month_in_days
+    Rails.cache.fetch("#{cache_key_with_version}/stats_usual_traitement_time_by_month_in_days", expires_in: 12.hours) do
+      usual_traitement_time_by_month_in_days
     end
   end
 
@@ -45,4 +57,51 @@ module ProcedureStatsConcern
         end
     end
   end
+
+  def traitement_times(date_range)
+    Traitement.for_traitement_time_stats(self)
+      .where(processed_at: date_range)
+      .pluck('dossiers.en_construction_at', :processed_at)
+      .map { |en_construction_at, processed_at| { en_construction_at: en_construction_at, processed_at: processed_at } }
+  end
+
+  def usual_traitement_time_by_month_in_days
+    traitement_times(first_processed_at..last_considered_processed_at)
+      .group_by { |t| t[:processed_at].beginning_of_month }
+      .transform_values { |month| month.map { |h| h[:processed_at] - h[:en_construction_at] } }
+      .transform_values { |traitement_times_for_month| traitement_times_for_month.percentile(USUAL_TRAITEMENT_TIME_PERCENTILE).ceil }
+      .transform_values { |seconds| seconds == 0 ? nil : seconds }
+      .transform_values { |seconds| convert_seconds_in_days(seconds) }
+      .transform_keys { |month| pretty_month(month) }
+  end
+
+  def usual_traitement_time_for_recent_dossiers(nb_days)
+    now = Time.zone.now
+    traitement_time =
+      traitement_times((now - nb_days.days)..now)
+        .map { |times| times[:processed_at] - times[:en_construction_at] }
+        .percentile(USUAL_TRAITEMENT_TIME_PERCENTILE)
+        .ceil
+
+    traitement_time = nil if traitement_time == 0
+    traitement_time
+  end
+
+  private
+
+  def first_processed_at
+    Traitement.for_traitement_time_stats(self).pick(:processed_at)
+  end
+
+  def last_considered_processed_at
+    (Time.zone.now - 1.month).end_of_month
+  end
+
+  def convert_seconds_in_days(seconds)
+    (seconds / 60.0 / 60.0 / 24.0).ceil
+  end
+
+  def pretty_month(month)
+    I18n.l(month, format: "%B %Y")
+  end
 end
diff --git a/app/models/procedure.rb b/app/models/procedure.rb
index 0af87e5a9..07ca5e6ff 100644
--- a/app/models/procedure.rb
+++ b/app/models/procedure.rb
@@ -565,19 +565,6 @@ class Procedure < ApplicationRecord
     end
   end
 
-  def usual_traitement_time
-    times = Traitement.includes(:dossier)
-      .where(dossier: self.dossiers)
-      .where.not('dossiers.en_construction_at' => nil, :processed_at => nil)
-      .where(processed_at: 1.month.ago..Time.zone.now)
-      .pluck('dossiers.en_construction_at', :processed_at)
-      .map { |(en_construction_at, processed_at)| processed_at - en_construction_at }
-
-    if times.present?
-      times.percentile(90).ceil
-    end
-  end
-
   def populate_champ_stable_ids
     TypeDeChamp
       .joins(:revisions)
diff --git a/app/models/traitement.rb b/app/models/traitement.rb
index 8bb604945..c382b9e79 100644
--- a/app/models/traitement.rb
+++ b/app/models/traitement.rb
@@ -19,10 +19,17 @@ class Traitement < ApplicationRecord
       .where("traitements.processed_at + (procedures.duree_conservation_dossiers_dans_ds * INTERVAL '1 month') - INTERVAL :expires_in < :now", { now: Time.zone.now, expires_in: Dossier::INTERVAL_BEFORE_EXPIRATION })
   end
 
+  scope :for_traitement_time_stats, -> (procedure) do
+    includes(:dossier)
+      .where(dossier: procedure.dossiers)
+      .where.not('dossiers.en_construction_at' => nil, :processed_at => nil)
+      .order(:processed_at)
+  end
+
   def self.count_dossiers_termines_by_month(groupe_instructeurs)
     last_traitements_per_dossier = Traitement
       .select('max(traitements.processed_at) as processed_at')
-      .where(dossier: Dossier.termine.where(groupe_instructeur: groupe_instructeurs))
+      .where(dossier: Dossier.state_termine.where(groupe_instructeur: groupe_instructeurs))
       .group(:dossier_id)
       .to_sql
 
diff --git a/app/services/pieces_justificatives_service.rb b/app/services/pieces_justificatives_service.rb
index 1d337f52c..08b358d4c 100644
--- a/app/services/pieces_justificatives_service.rb
+++ b/app/services/pieces_justificatives_service.rb
@@ -56,7 +56,9 @@ class PiecesJustificativesService
                 include_infos_administration: true,
                 dossier: dossier
               })
-    dossier.pdf_export_for_instructeur.attach(io: StringIO.open(pdf), filename: "export-#{dossier.id}.pdf", content_type: 'application/pdf')
+    ActiveRecord::Base.no_touching do
+      dossier.pdf_export_for_instructeur.attach(io: StringIO.open(pdf), filename: "export-#{dossier.id}.pdf", content_type: 'application/pdf')
+    end
     dossier.pdf_export_for_instructeur
   end
 
diff --git a/app/views/avis_mailer/avis_invitation.html.haml b/app/views/avis_mailer/avis_invitation.html.haml
index 52f08054d..319d0aa39 100644
--- a/app/views/avis_mailer/avis_invitation.html.haml
+++ b/app/views/avis_mailer/avis_invitation.html.haml
@@ -1,5 +1,5 @@
 - content_for(:title, 'Invitation à donner votre avis')
-- avis_link = @avis.expert.user.active?.present? ? expert_avis_url(@avis.procedure, @avis) : sign_up_expert_avis_url(@avis.procedure, @avis.id, @avis.expert.email)
+- avis_link = @avis.expert.user.active?.present? ? expert_avis_url(@avis.procedure, @avis) : sign_up_expert_avis_url(@avis.procedure, @avis.id, email: @avis.expert.email)
 
 - content_for(:footer) do
   Merci de ne pas répondre à cet email. Donnez votre avis
diff --git a/app/views/experts/avis/sign_up.html.haml b/app/views/experts/avis/sign_up.html.haml
index f93ed115f..3c4724d0b 100644
--- a/app/views/experts/avis/sign_up.html.haml
+++ b/app/views/experts/avis/sign_up.html.haml
@@ -4,7 +4,7 @@
       %p.description= @dossier.procedure.libelle
       %p.dossier Dossier nº #{@dossier.id}
     .column
-      = form_for(User.new, url: { controller: "experts/avis", action: :update_expert }, method: :post, html: { class: "form" }) do |f|
+      = form_for(User.new, url: sign_up_expert_avis_path(email: @email), method: :post, html: { class: "form" }) do |f|
         %h1 Créez-vous un compte
 
         = f.label :email, "Email"
diff --git a/app/views/instructeurs/procedures/_dossier_actions.html.haml b/app/views/instructeurs/procedures/_dossier_actions.html.haml
index 14983ffa8..710330bcb 100644
--- a/app/views/instructeurs/procedures/_dossier_actions.html.haml
+++ b/app/views/instructeurs/procedures/_dossier_actions.html.haml
@@ -1,4 +1,29 @@
-- if Dossier::EN_CONSTRUCTION_OU_INSTRUCTION.include?(state)
+- if Dossier::TERMINE.include?(state)
+  .dropdown.user-dossier-actions
+    %button.button.dropdown-button{ 'aria-expanded' => 'false', 'aria-controls' => 'actions-menu' }
+      Actions
+    #actions-menu.dropdown-content.fade-in-down
+      %ul.dropdown-items
+        - if archived
+          %li
+            = link_to unarchive_instructeur_dossier_path(procedure_id, dossier_id), method: :patch do
+              %span.icon.unarchive
+              .dropdown-description
+                Désarchiver le dossier
+        - else
+          %li
+            = link_to archive_instructeur_dossier_path(procedure_id, dossier_id), method: :patch do
+              %span.icon.archive
+              .dropdown-description
+                Archiver le dossier
+
+        %li.danger
+          = link_to supprimer_dossier_instructeur_dossier_path(procedure_id, dossier_id), method: :patch, data: { confirm: "Voulez vous vraiment supprimer le dossier #{dossier_id} ? Cette action est irréversible. \nNous vous suggérons de télécharger le dossier au format PDF au préalable." } do
+            %span.icon.delete
+            .dropdown-description
+              Supprimer le dossier
+
+- elsif Dossier::EN_CONSTRUCTION_OU_INSTRUCTION.include?(state)
   - if dossier_is_followed
     = link_to unfollow_instructeur_dossier_path(procedure_id, dossier_id), method: :patch, class: 'button' do
       %span.icon.unfollow>
@@ -7,13 +32,3 @@
     = link_to follow_instructeur_dossier_path(procedure_id, dossier_id), method: :patch, class: 'button' do
       %span.icon.follow>
       Suivre le dossier
-
-- elsif Dossier::TERMINE.include?(state)
-  - if archived
-    = link_to unarchive_instructeur_dossier_path(procedure_id, dossier_id), method: :patch, class: 'button' do
-      %span.icon.unarchive>
-      Désarchiver le dossier
-  - else
-    = link_to archive_instructeur_dossier_path(procedure_id, dossier_id), method: :patch, class: 'button' do
-      %span.icon.archive>
-      Archiver le dossier
diff --git a/app/views/shared/procedures/_stats.html.haml b/app/views/shared/procedures/_stats.html.haml
index fb6925914..2da3e10bc 100644
--- a/app/views/shared/procedures/_stats.html.haml
+++ b/app/views/shared/procedures/_stats.html.haml
@@ -11,15 +11,23 @@
         %span.big-number-card-number
           = distance_of_time_in_words(@usual_traitement_time)
         %span.big-number-card-detail
-          90% des demandes du mois dernier ont été traitées en moins de #{distance_of_time_in_words(@usual_traitement_time)}.
+          #{ProcedureStatsConcern::USUAL_TRAITEMENT_TIME_PERCENTILE}% des demandes des #{ProcedureStatsConcern::NB_DAYS_RECENT_DOSSIERS} derniers jours ont été traitées en moins de #{distance_of_time_in_words(@usual_traitement_time)}.
 
   .stat-cards
+    .stat-card.stat-card-half.pull-left
+      %span.stat-card-title TEMPS DE TRAITEMENT
+      .chart-container
+        .chart
+          - colors = %w(#C3D9FF #0069CC #1C7EC9) # from _colors.scss
+          = column_chart @usual_traitement_time_by_month, ytitle: "Nb Jours", legend: "bottom", label: "Temps de traitement entre le passage en instruction et la réponse (accepté, refusé, ou classé sans suite) pour 90% des dossiers"
+
     .stat-card.stat-card-half.pull-left
       %span.stat-card-title AVANCÉE DES DOSSIERS
       .chart-container
         .chart
           = area_chart @dossiers_funnel
 
+  .stat-cards
     .stat-card.stat-card-half.pull-left
       %span.stat-card-title TAUX D’ACCEPTATION
       .chart-container
@@ -27,9 +35,8 @@
           - colors = %w(#C3D9FF #0069CC #1C7EC9) # from _colors.scss
           = pie_chart @termines_states, colors: colors
 
-    .stat-cards
-      .stat-card.stat-card-half.pull-left
-        %span.stat-card-title RÉPARTITION PAR SEMAINE
-        .chart-container
-          .chart
-            = line_chart @termines_by_week, colors: ["#387EC3", "#AE2C2B", "#FAD859"]
+    .stat-card.stat-card-half.pull-left
+      %span.stat-card-title RÉPARTITION PAR SEMAINE
+      .chart-container
+        .chart
+          = line_chart @termines_by_week, colors: ["#387EC3", "#AE2C2B", "#FAD859"]
diff --git a/app/views/users/dossiers/show/_estimated_delay.html.haml b/app/views/users/dossiers/show/_estimated_delay.html.haml
index eabc51bb3..e33eab09c 100644
--- a/app/views/users/dossiers/show/_estimated_delay.html.haml
+++ b/app/views/users/dossiers/show/_estimated_delay.html.haml
@@ -4,8 +4,8 @@
 - show_time_means = procedure.id != procedure_id_for_which_we_hide_the_estimated_delay && procedure.path != procedure_path_for_which_we_hide_the_estimated_delay
 
 - cache(procedure.id, expires_in: 1.day) do
-  - if procedure.usual_traitement_time && show_time_means
+  - if procedure.usual_traitement_time_for_recent_dossiers(ProcedureStatsConcern::NB_DAYS_RECENT_DOSSIERS) && show_time_means
     %p
-      Habituellement, les dossiers de cette démarche sont traités dans un délai de #{distance_of_time_in_words(procedure.usual_traitement_time)}.
+      Habituellement, les dossiers de cette démarche sont traités dans un délai de #{distance_of_time_in_words(procedure.usual_traitement_time_for_recent_dossiers(ProcedureStatsConcern::NB_DAYS_RECENT_DOSSIERS))}.
     %p
-      Cette estimation est calculée automatiquement à partir des délais d’instruction constatés précédemment. Le délai réel peut être différent, en fonction du type de démarche (par exemple pour un appel à projet avec date de décision fixe).
+      Cette estimation est calculée automatiquement à partir des délais d’instruction constatés sur #{ProcedureStatsConcern::USUAL_TRAITEMENT_TIME_PERCENTILE}% des demandes qui ont été traitées lors des #{ProcedureStatsConcern::NB_DAYS_RECENT_DOSSIERS} derniers jours. Le délai réel peut être différent, en fonction du type de démarche (par exemple pour un appel à projet avec date de décision fixe).
diff --git a/config/routes.rb b/config/routes.rb
index 9dba2d095..22a203093 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -105,7 +105,8 @@ Rails.application.routes.draw do
   devise_scope :user do
     get '/users/no_procedure' => 'users/sessions#no_procedure'
     get 'connexion-par-jeton/:id' => 'users/sessions#sign_in_by_link', as: 'sign_in_by_link'
-    get 'lien-envoye/:email' => 'users/sessions#link_sent', constraints: { email: /.*/ }, as: 'link_sent'
+    get 'lien-envoye' => 'users/sessions#link_sent', as: 'link_sent'
+    get 'lien-envoye/:email' => 'users/sessions#link_sent', constraints: { email: /.*/ }, as: 'link_sent_legacy' # legacy, can be removed as soon as the previous line is deployed to production servers
     get '/users/password/reset-link-sent' => 'users/passwords#reset_link_sent'
   end
 
@@ -300,10 +301,6 @@ Rails.application.routes.draw do
   #
   scope module: 'experts', as: 'expert' do
     get 'avis', to: 'avis#index', as: 'all_avis'
-    # this redirections are ephemeral, to ensure that emails sent to experts before are still valid
-    # TODO : they will be removed in September, 2020
-    get 'avis/:id', to: redirect('/procedures/old/avis/%{id}')
-    get 'avis/:id/sign_up/email/:email', to: redirect("/procedures/old/avis/%{id}/sign_up/email/%{email}"), constraints: { email: /.*/ }
 
     resources :procedures, only: [], param: :procedure_id do
       member do
@@ -316,8 +313,13 @@ Rails.application.routes.draw do
             post 'avis' => 'avis#create_avis'
             get 'bilans_bdf'
 
-            get 'sign_up/email/:email' => 'avis#sign_up', constraints: { email: /.*/ }, as: 'sign_up'
-            post 'sign_up/email/:email' => 'avis#update_expert', constraints: { email: /.*/ }
+            get 'sign_up' => 'avis#sign_up'
+            post 'sign_up' => 'avis#update_expert'
+
+            # This redirections are ephemeral, to ensure that emails sent to experts before are still valid
+            # TODO : remove these lines after September, 2021
+            get 'sign_up/email/:email' => 'avis#sign_up', constraints: { email: /.*/ }, as: 'sign_up_legacy'
+            post 'sign_up/email/:email' => 'avis#update_expert', constraints: { email: /.*/ }, as: 'update_expert_legacy'
           end
         end
       end
@@ -329,11 +331,6 @@ Rails.application.routes.draw do
   #
 
   scope module: 'instructeurs', as: 'instructeur' do
-    # this redirections are ephemeral, to ensure that emails sent to experts before are still valid
-    # TODO : they will be removed in September, 2020
-    get 'avis/:id', to: redirect('/procedures/old/avis/%{id}')
-    get 'avis/:id/sign_up/email/:email', to: redirect("/procedures/old/avis/%{id}/sign_up/email/%{email}"), constraints: { email: /.*/ }
-
     resources :procedures, only: [:index, :show], param: :procedure_id do
       member do
         resources :groupes, only: [:index, :show], controller: 'groupe_instructeurs' do
diff --git a/lib/core_ext/array.rb b/lib/core_ext/array.rb
index 00aa9f59c..39d7ad777 100644
--- a/lib/core_ext/array.rb
+++ b/lib/core_ext/array.rb
@@ -17,7 +17,7 @@ class Array
     values = self.sort
 
     if values.empty?
-      return []
+      return 0
     elsif values.size == 1
       return values.first
     elsif p == 100
diff --git a/spec/features/experts/expert_spec.rb b/spec/features/experts/expert_spec.rb
index 6c2f45c05..c2aea0a66 100644
--- a/spec/features/experts/expert_spec.rb
+++ b/spec/features/experts/expert_spec.rb
@@ -12,7 +12,7 @@ feature 'Inviting an expert:' do
 
     context 'when I don’t already have an account' do
       scenario 'I can sign up' do
-        visit sign_up_expert_avis_path(avis.dossier.procedure, avis, avis.expert.email)
+        visit sign_up_expert_avis_path(avis.dossier.procedure, avis, email: avis.expert.email)
 
         expect(page).to have_field('Email', with: avis.expert.email, disabled: true)
         fill_in 'Mot de passe', with: 'This is a very complicated password !'
@@ -29,7 +29,7 @@ feature 'Inviting an expert:' do
         avis.expert.user.reload
       end
       scenario 'I can sign in' do
-        visit sign_up_expert_avis_path(avis.dossier.procedure, avis, avis.expert.email)
+        visit sign_up_expert_avis_path(avis.dossier.procedure, avis, email: avis.expert.email)
 
         expect(page).to have_current_path(new_user_session_path)
         login_as avis.expert.user, scope: :user
diff --git a/spec/features/instructeurs/expert_spec.rb b/spec/features/instructeurs/expert_spec.rb
index 20abe6017..84b3d56a6 100644
--- a/spec/features/instructeurs/expert_spec.rb
+++ b/spec/features/instructeurs/expert_spec.rb
@@ -45,7 +45,7 @@ feature 'Inviting an expert:', js: true do
 
       invitation_email = open_email(expert.email.to_s)
       avis = expert.avis.find_by(dossier: dossier)
-      sign_up_link = sign_up_expert_avis_path(avis.dossier.procedure, avis, avis.expert.email)
+      sign_up_link = sign_up_expert_avis_path(avis.dossier.procedure, avis, email: avis.expert.email)
       expect(invitation_email.body).to include(sign_up_link)
     end
 
diff --git a/spec/features/instructeurs/instruction_spec.rb b/spec/features/instructeurs/instruction_spec.rb
index 1b1bca949..190f8903d 100644
--- a/spec/features/instructeurs/instruction_spec.rb
+++ b/spec/features/instructeurs/instruction_spec.rb
@@ -66,6 +66,15 @@ feature 'Instructing a dossier:', js: true do
     dossier.reload
     expect(dossier.state).to eq(Dossier.states.fetch(:accepte))
     expect(dossier.motivation).to eq('a good reason')
+
+    click_on procedure.libelle
+    click_on 'traité'
+    click_on 'Actions'
+    accept_confirm do
+      click_on 'Supprimer le dossier'
+    end
+    click_on 'traité'
+    expect(page).not_to have_button('Actions')
   end
 
   scenario 'A instructeur can follow/unfollow a dossier' do
diff --git a/spec/mailers/avis_mailer_spec.rb b/spec/mailers/avis_mailer_spec.rb
index 6eac2062f..d9d822d5f 100644
--- a/spec/mailers/avis_mailer_spec.rb
+++ b/spec/mailers/avis_mailer_spec.rb
@@ -14,7 +14,7 @@ RSpec.describe AvisMailer, type: :mailer do
     it { expect(subject.body).to include(instructeur_avis_url(avis.dossier.procedure.id, avis)) }
 
     context 'when the recipient is not already registered' do
-      it { expect(subject.body).to include(sign_up_expert_avis_url(avis.dossier.procedure.id, avis.id, avis.expert.email)) }
+      it { expect(subject.body).to include(sign_up_expert_avis_url(avis.dossier.procedure.id, avis.id, email: avis.expert.email)) }
     end
 
     context 'when the dossier has been deleted before the avis was sent' do
diff --git a/spec/models/concern/procedure_stats_concern_spec.rb b/spec/models/concern/procedure_stats_concern_spec.rb
new file mode 100644
index 000000000..050989259
--- /dev/null
+++ b/spec/models/concern/procedure_stats_concern_spec.rb
@@ -0,0 +1,94 @@
+describe ProcedureStatsConcern do
+  describe '#usual_traitement_time_for_recent_dossiers' do
+    let(:procedure) { create(:procedure) }
+
+    before do
+      Timecop.freeze(Time.utc(2019, 6, 1, 12, 0))
+
+      delays.each do |delay|
+        create_dossier(construction_date: 1.week.ago - delay, instruction_date: 1.week.ago - delay + 12.hours, processed_date: 1.week.ago)
+      end
+    end
+
+    after { Timecop.return }
+
+    context 'when there are several processed dossiers' do
+      let(:delays) { [1.day, 2.days, 2.days, 2.days, 2.days, 3.days, 3.days, 3.days, 3.days, 12.days] }
+
+      it 'returns a time representative of the dossier instruction delay' do
+        expect(procedure.usual_traitement_time_for_recent_dossiers(30)).to be_between(3.days, 4.days)
+      end
+    end
+
+    context 'when there are very old dossiers' do
+      let(:delays) { [2.days, 2.days] }
+      let!(:old_dossier) { create_dossier(construction_date: 3.months.ago, instruction_date: 2.months.ago, processed_date: 2.months.ago) }
+
+      it 'ignores dossiers older than 1 month' do
+        expect(procedure.usual_traitement_time_for_recent_dossiers(30)).to be_within(1.hour).of(2.days)
+      end
+    end
+
+    context 'when there is a dossier with bad data' do
+      let(:delays) { [2.days, 2.days] }
+      let!(:bad_dossier) { create_dossier(construction_date: nil, instruction_date: nil, processed_date: 10.days.ago) }
+
+      it 'ignores bad dossiers' do
+        expect(procedure.usual_traitement_time_for_recent_dossiers(30)).to be_within(1.hour).of(2.days)
+      end
+    end
+
+    context 'when there is only one processed dossier' do
+      let(:delays) { [1.day] }
+      it { expect(procedure.usual_traitement_time_for_recent_dossiers(30)).to be_within(1.hour).of(1.day) }
+    end
+
+    context 'where there is no processed dossier' do
+      let(:delays) { [] }
+      it { expect(procedure.usual_traitement_time_for_recent_dossiers(30)).to eq nil }
+    end
+  end
+
+  describe '.usual_traitement_time_by_month_in_days' do
+    let(:procedure) { create(:procedure) }
+
+    def create_dossiers(delays_by_month)
+      delays_by_month.each_with_index do |delays, index|
+        delays.each do |delay|
+          processed_date = (index.months + 1.week).ago
+          create_dossier(construction_date: processed_date - delay, instruction_date: processed_date - delay + 12.hours, processed_date: processed_date)
+        end
+      end
+    end
+
+    before do
+      Timecop.freeze(Time.utc(2019, 6, 25, 12, 0))
+
+      create_dossiers(delays_by_month)
+    end
+
+    after { Timecop.return }
+
+    context 'when there are several processed dossiers' do
+      let(:delays_by_month) {
+  [
+    [90.days, 90.days],
+    [1.day, 2.days, 2.days, 2.days, 2.days, 3.days, 3.days, 3.days, 3.days, 12.days],
+    [30.days, 60.days, 60.days, 60.days]
+  ]
+}
+
+      it 'computes a time representative of the dossier instruction delay for each month except current month' do
+        expect(procedure.usual_traitement_time_by_month_in_days['avril 2019']).to eq 60
+        expect(procedure.usual_traitement_time_by_month_in_days['mai 2019']).to eq 4
+        expect(procedure.usual_traitement_time_by_month_in_days['juin 2019']).to eq nil
+      end
+    end
+  end
+
+  private
+
+  def create_dossier(construction_date:, instruction_date:, processed_date:)
+    dossier = create(:dossier, :accepte, procedure: procedure, en_construction_at: construction_date, en_instruction_at: instruction_date, processed_at: processed_date)
+  end
+end
diff --git a/spec/models/procedure_spec.rb b/spec/models/procedure_spec.rb
index 1f7327fdb..9850686d4 100644
--- a/spec/models/procedure_spec.rb
+++ b/spec/models/procedure_spec.rb
@@ -980,60 +980,6 @@ describe Procedure do
     end
   end
 
-  describe '#usual_traitement_time' do
-    let(:procedure) { create(:procedure) }
-
-    def create_dossier(construction_date:, instruction_date:, processed_date:)
-      dossier = create(:dossier, :accepte, procedure: procedure, en_construction_at: construction_date, en_instruction_at: instruction_date, processed_at: processed_date)
-    end
-
-    before do
-      Timecop.freeze(Time.utc(2019, 6, 1, 12, 0))
-
-      delays.each do |delay|
-        create_dossier(construction_date: 1.week.ago - delay, instruction_date: 1.week.ago - delay + 12.hours, processed_date: 1.week.ago)
-      end
-    end
-
-    after { Timecop.return }
-
-    context 'when there are several processed dossiers' do
-      let(:delays) { [1.day, 2.days, 2.days, 2.days, 2.days, 3.days, 3.days, 3.days, 3.days, 12.days] }
-
-      it 'returns a time representative of the dossier instruction delay' do
-        expect(procedure.usual_traitement_time).to be_between(3.days, 4.days)
-      end
-    end
-
-    context 'when there are very old dossiers' do
-      let(:delays) { [2.days, 2.days] }
-      let!(:old_dossier) { create_dossier(construction_date: 3.months.ago, instruction_date: 2.months.ago, processed_date: 2.months.ago) }
-
-      it 'ignores dossiers older than 1 month' do
-        expect(procedure.usual_traitement_time).to be_within(1.hour).of(2.days)
-      end
-    end
-
-    context 'when there is a dossier with bad data' do
-      let(:delays) { [2.days, 2.days] }
-      let!(:bad_dossier) { create_dossier(construction_date: nil, instruction_date: nil, processed_date: 10.days.ago) }
-
-      it 'ignores bad dossiers' do
-        expect(procedure.usual_traitement_time).to be_within(1.hour).of(2.days)
-      end
-    end
-
-    context 'when there is only one processed dossier' do
-      let(:delays) { [1.day] }
-      it { expect(procedure.usual_traitement_time).to be_within(1.hour).of(1.day) }
-    end
-
-    context 'where there is no processed dossier' do
-      let(:delays) { [] }
-      it { expect(procedure.usual_traitement_time).to be_nil }
-    end
-  end
-
   describe '.ensure_a_groupe_instructeur_exists' do
     let!(:procedure) { create(:procedure) }
 
@@ -1082,12 +1028,12 @@ describe Procedure do
     it 'estimates average dossier weight' do
       expect(procedure.reload.average_dossier_weight).to eq 5
     end
+  end
 
-    private
+  private
 
-    def create_dossier_with_pj_of_size(size, procedure)
-      dossier = create(:dossier, :accepte, procedure: procedure)
-      create(:champ_piece_justificative, size: size, dossier: dossier)
-    end
+  def create_dossier_with_pj_of_size(size, procedure)
+    dossier = create(:dossier, :accepte, procedure: procedure)
+    create(:champ_piece_justificative, size: size, dossier: dossier)
   end
 end
diff --git a/spec/models/traitement_spec.rb b/spec/models/traitement_spec.rb
index 42465e8b1..d84bdeedc 100644
--- a/spec/models/traitement_spec.rb
+++ b/spec/models/traitement_spec.rb
@@ -2,23 +2,28 @@ describe Traitement do
   describe '#count_dossiers_termines_by_month' do
     let(:procedure) { create(:procedure, :published, groupe_instructeurs: [groupe_instructeurs]) }
     let(:groupe_instructeurs) { create(:groupe_instructeur) }
-    let(:result) { Traitement.count_dossiers_termines_by_month(groupe_instructeurs) }
 
     before do
       create_dossier_for_month(procedure, 2021, 3)
       create_dossier_for_month(procedure, 2021, 3)
+      create_archived_dossier_for_month(procedure, 2021, 3)
       create_dossier_for_month(procedure, 2021, 2)
-      Timecop.freeze(Time.zone.local(2021, 3, 5))
+    end
+
+    subject do
+      Timecop.freeze(Time.zone.local(2021, 3, 5)) do
+        Traitement.count_dossiers_termines_by_month(groupe_instructeurs)
+      end
     end
 
     it 'count dossiers_termines by month' do
-      expect(count_for_month(result, 3)).to eq 2
-      expect(count_for_month(result, 2)).to eq 1
+      expect(count_for_month(subject, 3)).to eq 3
+      expect(count_for_month(subject, 2)).to eq 1
     end
 
     it 'returns descending order by month' do
-      expect(result[0]["month"].to_date.month).to eq 3
-      expect(result[1]["month"].to_date.month).to eq 2
+      expect(subject[0]["month"].to_date.month).to eq 3
+      expect(subject[1]["month"].to_date.month).to eq 2
     end
   end
 
@@ -31,7 +36,14 @@ describe Traitement do
   end
 
   def create_dossier_for_month(procedure, year, month)
-    Timecop.freeze(Time.zone.local(year, month, 5))
-    create(:dossier, :accepte, :with_attestation, procedure: procedure)
+    Timecop.freeze(Time.zone.local(year, month, 5)) do
+      create(:dossier, :accepte, :with_attestation, procedure: procedure)
+    end
+  end
+
+  def create_archived_dossier_for_month(procedure, year, month)
+    Timecop.freeze(Time.zone.local(year, month, 5)) do
+      create(:dossier, :accepte, :archived, :with_attestation, procedure: procedure)
+    end
   end
 end
diff --git a/spec/services/pieces_justificatives_service_spec.rb b/spec/services/pieces_justificatives_service_spec.rb
index b4e7b01a9..652ea9819 100644
--- a/spec/services/pieces_justificatives_service_spec.rb
+++ b/spec/services/pieces_justificatives_service_spec.rb
@@ -44,4 +44,18 @@ describe PiecesJustificativesService do
       expect(subject.any? { |piece| piece.name == 'serialized' }).to be_truthy
     end
   end
+
+  describe '.generate_dossier_export' do
+    subject { PiecesJustificativesService.generate_dossier_export(dossier) }
+    it "generates pdf export for instructeur" do
+      subject
+      expect(dossier.pdf_export_for_instructeur).to be_attached
+    end
+
+    it "doesn't update dossier" do
+      before_export = Time.zone.now
+      subject
+      expect(dossier.updated_at).to be <= before_export
+    end
+  end
 end
diff --git a/spec/views/users/dossiers/show/_status_overview.html.haml_spec.rb b/spec/views/users/dossiers/show/_status_overview.html.haml_spec.rb
index 71362ea7d..5f95bd3b7 100644
--- a/spec/views/users/dossiers/show/_status_overview.html.haml_spec.rb
+++ b/spec/views/users/dossiers/show/_status_overview.html.haml_spec.rb
@@ -1,5 +1,5 @@
 describe 'users/dossiers/show/_status_overview.html.haml', type: :view do
-  before { allow(dossier.procedure).to receive(:usual_traitement_time).and_return(1.day) }
+  before { allow(dossier.procedure).to receive(:usual_traitement_time_for_recent_dossiers).and_return(1.day) }
 
   subject! { render 'users/dossiers/show/status_overview.html.haml', dossier: dossier }
 
diff --git a/yarn.lock b/yarn.lock
index e67528021..93c0ca786 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3248,15 +3248,7 @@ chalk@^3.0.0, chalk@^3.0.0-beta.2:
     ansi-styles "^4.1.0"
     supports-color "^7.1.0"
 
-chalk@^4.0.0:
-  version "4.0.0"
-  resolved "https://registry.yarnpkg.com/chalk/-/chalk-4.0.0.tgz#6e98081ed2d17faab615eb52ac66ec1fe6209e72"
-  integrity sha512-N9oWFcegS0sFr9oh1oz2d7Npos6vNoWW9HvtCg5N1KRFpUhaAhvTv5Y58g880fZaEYSNm3qDz8SU1UrGvp+n7A==
-  dependencies:
-    ansi-styles "^4.1.0"
-    supports-color "^7.1.0"
-
-chalk@^4.1.0:
+chalk@^4.0.0, chalk@^4.1.0:
   version "4.1.0"
   resolved "https://registry.yarnpkg.com/chalk/-/chalk-4.1.0.tgz#4e14870a618d9e2edd97dd8345fd9d9dc315646a"
   integrity sha512-qwx12AxXe2Q5xQ43Ac//I6v5aXTipYrSESdOgzrN+9XjgEpyjpKuvSGaN4qE93f7TQTlerQQ8S+EQ0EyDoVL1A==
@@ -10090,9 +10082,9 @@ postcss-values-parser@^2.0.0, postcss-values-parser@^2.0.1:
     uniq "^1.0.1"
 
 postcss@^7.0.0, postcss@^7.0.1, postcss@^7.0.14, postcss@^7.0.16, postcss@^7.0.17, postcss@^7.0.2, postcss@^7.0.26, postcss@^7.0.27, postcss@^7.0.5, postcss@^7.0.6:
-  version "7.0.30"
-  resolved "https://registry.yarnpkg.com/postcss/-/postcss-7.0.30.tgz#cc9378beffe46a02cbc4506a0477d05fcea9a8e2"
-  integrity sha512-nu/0m+NtIzoubO+xdAlwZl/u5S5vi/y6BCsoL8D+8IxsD3XvBS8X4YEADNIVXKVuQvduiucnRv+vPIqj56EGMQ==
+  version "7.0.36"
+  resolved "https://registry.yarnpkg.com/postcss/-/postcss-7.0.36.tgz#056f8cffa939662a8f5905950c07d5285644dfcb"
+  integrity sha512-BebJSIUMwJHRH0HAQoxN4u1CN86glsrwsW0q7T+/m44eXOUAxSNdHRkNZPYz5vVUbg17hFgOQDE7fZk7li3pZw==
   dependencies:
     chalk "^2.4.2"
     source-map "^0.6.1"