Track External Links with Google Analytics

ga-ext.js

var gaParentDiv = ""; // Only change links in this selector including trailing space.
var trackingBase = "/ext/"; 
$(parentDiv+"a[href^=http\\:\\/\\/]:not(a[href*=\\/"+document.domain+"])").click(function () {
    pageTracker._trackPageview(trackingBase+$(this).attr("href"));
    });