Reversing a google analytics ecommerce transaction, This code snippet should be added to the header.tpl in the ganalytics module.

header.tpl

<script type="text/javascript">
  var _gaq = _gaq || [];
  _gaq.push(['_setAccount', 'UA-XXXXX-X']);
  _gaq.push(['_trackPageview']);

	_gaq.push(['_addTrans',
	   '1234',           // order ID - required
	   'Womens Apparel', // affiliation or store name
	   '-28.28',          // total - required
	   '-1.29',           // tax
	   '-15.00',          // shipping
	   'San Jose',       // city
	   'California',     // state or province
	   'USA'             // country
	]);
	_gaq.push(['_addItem',
	   '1234',           // order ID - necessary to associate item with transaction
	   'DD44',           // SKU/code - required
	   'T-Shirt',        // product name
	   'Olive Medium',   // category or variation
	   '11.99',          // unit price - required
	   '-1'               // item quantity - required
	]);
	_gaq.push(['_trackTrans']);

  (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);
  })();