diff --git a/src/setting_defines.h b/src/setting_defines.h
--- a/src/setting_defines.h
+++ b/src/setting_defines.h
@@ -1,5 +1,5 @@
 /*
-  Copyright © 2017 Hasan Yavuz Özderya
+  Copyright © 2018 Hasan Yavuz Özderya
 
   This file is part of serialplot.
 
@@ -106,6 +106,7 @@ const char SG_Record_StopOnClose[]      
 const char SG_Record_Header[]           = "header";
 const char SG_Record_Separator[]        = "separator";
 const char SG_Record_DisableBuffering[] = "disableBuffering";
+const char SG_Record_Timestamp[]        = "timestamp";
 
 // update check settings keys
 const char SG_UpdateCheck_Periodic[]  = "periodicCheck";