diff --git a/plugin/makecols.vim b/plugin/makecols.vim
index 18b9a53..c5cadcd 100644
--- a/plugin/makecols.vim
+++ b/plugin/makecols.vim
@@ -88,12 +88,10 @@ function! s:convert_selection_vert()
         let cols = g:makecols_cols
         let sec = get(old_selection, c, "")
         let i = 0
-        while i <= cols
-            let z = i
+        while i <= lines
             let i = i + rows
             let sec = get(old_selection, i, "")
             let new_string = join([new_string, sec], "\t")
-            let i = z+1
         endwhile
         let new_string = join([new_string,""], "\n")
         let c += 1