Please look at this document:
http://cura.free.fr/gauq/11gdcura.html#**
This link starts you with the English intro., which is half-way down the document. If you are interested in specifics, you can scroll up to the top, where you will find links to specific birth data, in 15,943 cases.
I think this study is rather unassailable, from any point of view.
Om Tryamnbakam Yajamahe viveshwar