I am pretty sure those numbers doesn't exist and even if they did they would be meaningless. Company culture is very unique and based on specific people being involved. One person can literally make or break the companies productivity and success.

I think the real point to be made anyway is that there isn't any numbers showing that remote work is in itself making productivity worse.

Sometimes you need to reboot (ex. Yahoo) but mostly if you have good people with good ethics it's just as good as any other setup.