It really depends on what assumptions you are making, your basis of comparison, and how you measure performance.

Does X perform better than Y in general or within the community. Does hiring match national population, the applicant pool, or the top 1% of the applicant pool? How do you measure performance?

These topics are rarely fleshed out in any public corporate policy. All I know is my bonus depends on increasing the % of minority employees.

I don’t think it’s obvious that summary statistics will be helpful unless they’re particularly carefully done. Where do averages come from? If individual data points are biased in the same direction (that is, not noise that cancels out) then the group average will be too.

This isn’t something you can just assume when you see someone quoting statistics. It could be a garbage study.

Is the Google applicant pool a representative sample of the group at large?