diff --git a/etc/requirements.txt b/etc/requirements.txt
index 59227a29..8b969b06 100644
--- a/etc/requirements.txt
+++ b/etc/requirements.txt
@@ -7,7 +7,7 @@ blist==1.3.4
 
 # Scientific Libraries
 
-pytz==2013b
+pytz==2013.8
 numpy==1.7.1
 
 pandas==0.12.0