Awesome GA Scroll Tracker

//This script is taken from http://www.savio.no/blogg/a/114/tracking-content-scrollers-scanners-og-readers-in-google-analytics   Worthwhile read.  Also Eivind Savio notes that the ORIGINAL innovator of this script was Thomas Baekdal (www.baekdal.com)

// This script was originally written by Justin Cutroni, see http://cutroni.com/blog/2012/02/21/advanced-content-tracking-with-google-analytics-part-1/

var readerTime = 30; // Seconds after scroll to bottom of content before visitor is classified as "Reader"
var readerLocation = 150; // # px before tracking a reader
var callBackTime = 100; // Default time delay before checking location
// Set some flags for tracking & execution
var timer = 0;
var contentLength = 0; // Content Length -> Length of content area
var scroller = false;
var endContent = false;
var didComplete = false;
// Set some time variables to calculate reading time etc.
var pageTimeLoad = 0;
var scrollTimeStart = 0;
var timeToScroll = 0;
var contentTime = 0;
var endTime = 0;
jQuery(function($) {
// Check if content has to be scrolled
if ($(window).height() < $('#contentArea').height()) { // Replace contentArea with the name (class or ID) of your content wrappers name
pageTimeLoad = new Date().getTime();
contentLength = $('#contentArea').height();
_gaq.push(['_trackEvent','Page Scroll','Page Scroll: Allowed',window.location.pathname,contentLength,true]);
}
// Check the location and track user
function trackLocation() {
bottom = $(window).height() + $(window).scrollTop();
height = $(document).height();
// If user has scrolled beyond threshold send an event
if (bottom > readerLocation && !scroller) {
scroller = true;
scrollTimeStart = new Date().getTime();
if (pageTimeLoad > 0) {
timeToScroll = Math.round((scrollTimeStart-pageTimeLoad)/1000);
} else {
timeToScroll = ""
}
// Article scroll started
_gaq.push(['_trackEvent','Page Scroll','Page Scroll: Started',window.location.pathname,timeToScroll,true]);
}
// If user has hit the bottom of the content send an event
if (bottom >= $('#contentArea').scrollTop() + $('#contentArea').innerHeight() && !endContent) {
timeToScroll = new Date().getTime();
contentTime = Math.round((timeToScroll-scrollTimeStart)/1000);
if (contentTime < readerTime) {
_gaq.push(['_setCustomVar',1,'ReaderType','Scanner',3]);
_gaq.push(['_trackEvent','Page Scroll','Page Scroll: Content Scanner',window.location.pathname,contentTime,true]);
} else {
_gaq.push(['_setCustomVar',1,'ReaderType','Reader',3]);
_gaq.push(['_trackEvent','Page Scroll','Page Scroll: Content Reader',window.location.pathname,contentTime,true]);
}
endContent = true;
}
// If user has hit the bottom send an event
if (bottom == height && !didComplete) {
endTime = new Date().getTime();
totalTime = Math.round((endTime - scrollTimeStart)/1000);
_gaq.push(['_trackEvent','Page Scroll','Page Scroll: Page Bottom',window.location.pathname,totalTime,true]);
didComplete = true;
}
}
// Track the scrolling and track location
$(window).scroll(function() {
if (timer) {
clearTimeout(timer);
}
// Use a buffer so we don't call trackLocation too often.
timer = setTimeout(trackLocation, callBackTime);
});
});