diff --git a/collector/helper_test.go b/collector/helper_test.go
index 48a4f7c4..0424d480 100644
--- a/collector/helper_test.go
+++ b/collector/helper_test.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Prometheus Authors
+// Copyright 2020 The Prometheus Authors
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at