diff --git a/lib/node-progress.js b/lib/node-progress.js
index <HASH>..<HASH> 100644
--- a/lib/node-progress.js
+++ b/lib/node-progress.js
@@ -67,7 +67,8 @@ function ProgressBar(fmt, options) {
  */
 
 ProgressBar.prototype.tick = function(len, tokens){
-  len = len || 1;
+  if (len !== 0)
+    len = len || 1;
 
   // swap tokens
   if ('object' == typeof len) tokens = len, len = 1;
Added ability to tick by zero chunks - tick(0)