diff --git a/units/tmp.mount b/units/tmp.mount
index 4e1bb8de24..734acea237 100644
--- a/units/tmp.mount
+++ b/units/tmp.mount
@@ -22,4 +22,4 @@ After=swap.target
 What=tmpfs
 Where=/tmp
 Type=tmpfs
-Options=mode=1777,strictatime,nosuid,nodev,size=50%,nr_inodes=1m
+Options=mode=1777,strictatime,nosuid,nodev,size=50%%,nr_inodes=1m