diff --git a/lib/tput.js b/lib/tput.js
index 395cca0..8e6fb57 100644
--- a/lib/tput.js
+++ b/lib/tput.js
@@ -984,7 +984,9 @@ Tput.prototype._compile = function(info, key, str) {
     if (read(/^%([+\-*\/m&|\^=><])/)) {
       if (ch === '=') ch = '===';
       else if (ch === 'm') ch = '%';
-      expr('(stack.push(v = (stack.pop() ' + ch + ' stack.pop()) || 0), v)');
+      expr('(v = stack.pop(),'
+        + ' stack.push(v = (stack.pop() ' + ch + ' v) || 0),'
+        + ' v)');
       continue;
     }