diff --git a/zipline/finance/performance/tracker.py b/zipline/finance/performance/tracker.py
index a6cf6bf0..6cfadb19 100644
--- a/zipline/finance/performance/tracker.py
+++ b/zipline/finance/performance/tracker.py
@@ -138,7 +138,7 @@ class PerformanceTracker(object):
             # period
             keep_transactions=False,
             keep_orders=False,
-            # don't serialize positions for cumualtive period
+            # don't serialize positions for cumulative period
             serialize_positions=False,
             asset_finder=self.env.asset_finder,
         )