diff --git a/app/services/create_stats.rb b/app/services/create_stats.rb
index a985dd71..5a18dcdb 100644
--- a/app/services/create_stats.rb
+++ b/app/services/create_stats.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 
 class CreateStats
   attr_reader :years, :months, :user