diff --git a/spectrum.py b/spectrum.py
index 1265b23..471fbe2 100755
--- a/spectrum.py
+++ b/spectrum.py
@@ -658,7 +658,7 @@ mean_bias = sp_convolve(
         50,
     )     ,
     'same',
-) / 50
+) / 50 * 0
 
 data[
                            :                       ,