diff --git a/lib/feedback.py b/lib/feedback.py
index 2eb0a86d8937fb78c983038e96a3c9e37fe6e7e7..8692c0af45d5d8946d6a7d2b1374f07057c0cbc1 100644
--- a/lib/feedback.py
+++ b/lib/feedback.py
@@ -53,7 +53,7 @@ class Feedback():
 
     # determine duration in ISO format (couldn't find a nice lib for it)
     def __convert_timedelta_to_iso(self, td):
-        y,w,d,h,m,s = td.days/365, (td.days/7)%365, (td.days/7)%7, td.seconds/3600, (td.seconds/60)%60, td.seconds%60
+        y,w,d,h,m,s = td.days//365, (td.days//7)%365, (td.days//7)%7, td.seconds//3600, (td.seconds//60)%60, td.seconds%60
         duration = 'P{}Y{}M{}DT{}H{}M{}S'.format(y,w,d,h,m,s)
         return duration