diff --git a/app/controllers/stats_controller.rb b/app/controllers/stats_controller.rb
index d6be1be0..a2490acc 100644
--- a/app/controllers/stats_controller.rb
+++ b/app/controllers/stats_controller.rb
@@ -377,7 +377,7 @@ class StatsController < ApplicationController
   # the block should return an array of indexes each is added to the hash and summed
   def convert_to_array(records, upper_bound)
     a = Array.new(upper_bound, 0)
-    records.each { |r| (yield r).each { |i| a[i] += 1 } }
+    records.each { |r| (yield r).each { |i| a[i] += 1 if a[i] } }
     a
   end
   
diff --git a/test/controllers/stats_controller_test.rb b/test/controllers/stats_controller_test.rb
index aacef8be..20add95c 100644
--- a/test/controllers/stats_controller_test.rb
+++ b/test/controllers/stats_controller_test.rb
@@ -142,6 +142,28 @@ class StatsControllerTest < ActionController::TestCase
     end
   end
 
+  def test_empty_last12months_data
+    Timecop.travel(Time.local(2013, 1, 15)) do
+      login_as(:admin_user)
+      @current_user = User.find(users(:admin_user).id)
+      @current_user.todos.delete_all
+      given_todos_for_stats
+      get :actions_done_last12months_data
+      assert_response :success
+    end
+  end
+
+  def test_out_of_bounds_events_for_last12months_data
+    login_as(:admin_user)
+    @current_user = User.find(users(:admin_user).id)
+    @current_user.todos.delete_all
+    create_todo_in_past(2.years)
+    create_todo_in_past(15.months)
+
+    get :actions_done_last12months_data
+    assert_response :success
+  end
+
   def test_actions_done_last30days_data
     login_as(:admin_user)
     @current_user = User.find(users(:admin_user).id)