GA: Rank Tracking Based on User visits

gistfile1.html

<script type="text/javascript">
if (document.referrer.match(/google.com/gi) && document.referrer.match(/cd/gi)) {
  var myString = document.referrer;
  var r        = myString.match(/cd=(.*?)&/);
  var rank     = parseInt(r[1]);
  var kw       = myString.match(/q=(.*?)&/);
  
  if (kw[1].length > 0) {
    var keyWord  = decodeURI(kw[1]);
  } else {
    keyWord = "(not provided)";
  }

  var p        = document.location.pathname;
  _gaq.push(['_trackEvent', 'RankTracker', keyWord, p, rank, true]);
}
</script>