diff --git a/web/html/addvote.php b/web/html/addvote.php
index 70280cfd..3e4def44 100644
--- a/web/html/addvote.php
+++ b/web/html/addvote.php
@@ -69,7 +69,7 @@ if (has_credential(CRED_TU_ADD_VOTE)) {
 
     if (!empty($_POST['addVote']) && empty($error)) {
         // Convert $quorum to a String of maximum length "12.34" (5).
-        $quorum_str = substr(strval($quorum), min(5, strlen($quorum));
+        $quorum_str = substr(strval($quorum), min(5, strlen($quorum)));
         add_tu_proposal($_POST['agenda'], $_POST['user'],
                         $len, $quorum_str, $uid);