diff --git a/sc2reader/resources.py b/sc2reader/resources.py
index 22de4adf..a74445fc 100644
--- a/sc2reader/resources.py
+++ b/sc2reader/resources.py
@@ -430,9 +430,8 @@ def load_details(self):
 
         self.game_length = self.length
         self.real_length = utils.Length(
-            seconds=int(
-                self.length.seconds / GAME_SPEED_FACTOR[self.expansion][self.speed]
-            )
+            seconds=self.length.seconds
+            // GAME_SPEED_FACTOR[self.expansion].get(self.speed, 1.0)
         )
         self.start_time = datetime.utcfromtimestamp(
             self.unix_timestamp - self.real_length.seconds