It was only in my last post that I was lamenting the lack of data on Facebook advertising effectiveness. I´ve only got time for a very short post today, but this news came across my virtual desk (or traveling desk, as I´m a long way from home) today.
Probably worth scanning in more detail of you have more time than I do right now. And don´t forget what I wrote in that last post - good copy, good segmentation and a time specific call to action will overcome bad macro stats like the ones above every time.