diff --git a/anki/graphs.py b/anki/graphs.py
index 8b7decbc8..ff2012c0e 100644
--- a/anki/graphs.py
+++ b/anki/graphs.py
@@ -189,7 +189,8 @@ where type = 1""")
         fig = Figure(figsize=(self.width, self.height), dpi=self.dpi)
         times = self.stats['dayTimes']
         self.addMissing(times, -days, 0)
-        times = self.unzip(times.items())
+        times = self.unzip([(day,y) for (day,y) in times.items()
+                            if day + days >= 0])
         graph = fig.add_subplot(111)
         self.filledGraph(graph, days, reviewTimeC, *times)
         graph.set_xlim(xmin=-days, xmax=0)