diff --git a/helpers/trendings_helper.py b/helpers/trendings_helper.py
index 56fda34..3e70ae3 100644
--- a/helpers/trendings_helper.py
+++ b/helpers/trendings_helper.py
@@ -163,7 +163,9 @@ class Trendings_helper:
     # In contrary of getGenericTrending, it regroups items in the format: {item, start: timestamp1, end: timestamp2}
     # so that it can be displayed easily on the timeline.
     def getGenericTrendingOvertime(self, dateS, dateE, choice=None, topNum=0):
-        if choice == 'tags':
+        if choice == 'categs':
+            trendingType = self.keyCateg
+        elif choice == 'tags':
             trendingType = self.keyTag
         else:
             trendingType = self.keyEvent
diff --git a/templates/trendings.html b/templates/trendings.html
index 6601dd0..c9f2815 100644
--- a/templates/trendings.html
+++ b/templates/trendings.html
@@ -215,6 +215,7 @@ small {
                                 <b>Timeline:</b>
                                 <select id="timeline_selector">
                                         <option value="events" selected="">Events</option>
+                                        <option value="categs">Categories</option>
                                         <option value="tags">Tags</option>
                                 </select>
                             </div>