If you got an email from Google today with the subject line: “Changes to setVar variable and impact on metrics“, you might be wondering what all the fuss is about.
Summary:
Google Analytics (GA) was not reporting an accurate bounce rate when the _setVar() script was called to track a user defined variable. Here is an obvious example of the reporting error issue:
Why was this happening?
The “_setVar” function is a JavaScript call that modifies the _utmv cookie and is used for setting a user defined value in GA.
The problem arises when the _setVar script wants to share all its great data with GA while the _trackPageview() script also wants to share its data with GA. The combined data is accurate to report a single page view, but since GA got more than one “interaction hit” it eliminates the possibility for the page visit to be counted as a bounce.
This is what the email means by “Starting Wednesday, January 27, 2009 a call to the _setVar method will no longer be counted as an interaction hit“.
