diff --git a/app/helpers/announcements_helper.rb b/app/helpers/announcements_helper.rb
index 0272c8f..05989c4 100644
--- a/app/helpers/announcements_helper.rb
+++ b/app/helpers/announcements_helper.rb
@@ -181,7 +181,7 @@ module AnnouncementsHelper
       announcements = announcements.sort_by { |announcement|
           tmp1 = announcement["postdate"].blank?
           [
-            -a['sort_number'].to_i,
+            -announcement['sort_number'].to_i,
             tmp1 ? 0 : 1, tmp1 ? nil : announcement["postdate"].to_time
           ]
         }.reverse