diff --git a/rectangular-region-mode.el b/rectangular-region-mode.el
index 675b498..d0c3c8d 100644
--- a/rectangular-region-mode.el
+++ b/rectangular-region-mode.el
@@ -68,13 +68,13 @@
          (anchor-line (save-excursion (goto-char rrm/anchor) (line-number-at-pos)))
          (left-column (if (< point-column anchor-column) point-column anchor-column))
          (right-column (if (> point-column anchor-column) point-column anchor-column))
-         (navigation-func (if (< point-line anchor-line) 'next-line 'previous-line)))
+         (navigation-step (if (< point-line anchor-line) 1 -1)))
     (move-to-column anchor-column)
     (set-mark (point))
     (move-to-column point-column)
     (mc/save-excursion
      (while (not (= anchor-line (line-number-at-pos)))
-       (funcall navigation-func)
+       (forward-line navigation-step)
        (move-to-column anchor-column)
        (when (= anchor-column (current-column))
          (set-mark (point))