diff --git a/OpenRa.Game/Exts.cs b/OpenRa.Game/Exts.cs
index cc04e81a91..3de1b767a5 100644
--- a/OpenRa.Game/Exts.cs
+++ b/OpenRa.Game/Exts.cs
@@ -25,7 +25,7 @@ namespace OpenRa.Game
 
 		public static float Product(this IEnumerable<float> xs)
 		{
-			return xs.Aggregate((a, x) => a * x);
+			return xs.Aggregate(1f, (a, x) => a * x);
 		}
 	}
 }