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app/helpers/etablissement_helper.rb

@@ -33,4 +33,8 @@ module EtablissementHelper
       '53' => '10 000 salariés et plus'
     }[etablissement.entreprise_code_effectif_entreprise]
   end
+
+  def pretty_date_exercice(date)
+    date.sub(/(?<year>\d{4})(?<month>\d{2})/, '\k<month>/\k<year>') if date.present?
+  end
 end