diff --git a/Recyclable.Collections.Benchmarks/RecyclableBenchmarkBase.cs b/Recyclable.Collections.Benchmarks/RecyclableBenchmarkBase.cs
index 28a163f..01d2bf7 100644
--- a/Recyclable.Collections.Benchmarks/RecyclableBenchmarkBase.cs
+++ b/Recyclable.Collections.Benchmarks/RecyclableBenchmarkBase.cs
@@ -7,6 +7,7 @@ namespace Recyclable.Collections.Benchmarks
 {
 	public enum RecyclableCollectionsBenchmarkSource
 	{
+		Unknown,
 		Array,
 		List,
 		PooledList,