diff --git a/requirements.txt b/requirements.txt
index 046f47322..1a307b2cc 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -17,7 +17,7 @@ pytest-mock==1.6.3
 pytest-cov==2.5.1
 hyperopt==0.1
 # do not upgrade networkx before this is fixed https://github.com/hyperopt/hyperopt/issues/325
-networkx==2.0
+networkx==1.11
 tabulate==0.8.1
 
 # Required for plotting data