FIX a discount is a percent, not an amount, so we use vatrate not price

htdocs/core/lib/functions2.lib.php

@@ -1471,7 +1471,7 @@ function dol_print_reduction($reduction,$langs)
     }
     else
     {
-        $string = price($reduction).'%';
+    	$string = vatrate($reduction,true);
     }
 
     return $string;