Google Analytics _setCustomVars

Question

<script type="text/javascript">
var _gaq = _gaq || [];

_gaq.push(['_setAccount', 'UA-xxxxxxxxx-x']);

_gaq.push(['_setDomainName', 'none']);

_gaq.push(['_setAllowLinker', true]);

_gaq.push(['_setCustomVar',1,'z','100',1]);

_gaq.push(['_trackPageview']);


(function() {
  var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true;
  ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js';
  var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s);
})();

User defined value is not shown in GA statistics for more than 3 days. What is the problem with my code