Does Google Analytics have performance overhead?

Question

To what extent does Google Analytics impact performance?

I\'m looking for the following:

• Benchmarks (including response times/pageload times et al)

Answer 1

Well, I have have searched, researched and expored extensively on net. But I have not found any statistical data that claims either in favour or against of the premise.

However, this excerpt from http://www.ga-experts.com claims that its a Myth that GA slows down your website.

Err, well okay, maybe slightly, but we’re talking about milliseconds. GA works by page tagging, and any time you add more content to a web page, it will increase loading times. However if you follow best practice (adding the tag before the tag) then your page will load first. Also, bear in mind that any page tag based web analytics package (which is the majority) will work the same way

From the answers above and all other sources, what I feel is that whatever slowdown it causes in not percieved by the user as the Script is included at the bottom of the page. But if we talk of complete page-loads we might say that it slows down the page-load time.

Please post in more info if you have and DATA if you have any.