diff --git a/src/engine.h b/src/engine.h
index 3dfe22845a66ba02fcc270e13647efd4390c7256..da3d076da5d21d762487e3b8a85455886496a54c 100644
--- a/src/engine.h
+++ b/src/engine.h
@@ -146,6 +146,7 @@ struct engine {
 
   /* Statistics information */
   FILE *file_stats;
+  FILE *file_timesteps;
   double timeLastStatistics;
   double deltaTimeStatistics;