diff --git a/runtime/doc/vi_diff.txt b/runtime/doc/vi_diff.txt
index 4332706..1714833 100644
--- a/runtime/doc/vi_diff.txt
+++ b/runtime/doc/vi_diff.txt
@@ -1,4 +1,4 @@
-*vi_diff.txt*   For Vim version 9.0.  Last change: 2022 Apr 03
+*vi_diff.txt*   For Vim version 9.1.  Last change: 2022 Apr 03
 
 
 		  VIM REFERENCE MANUAL    by Bram Moolenaar