Diversity Numbes is a phrase used by the elite to describe the degree to which a business’s or organization's workforce is not straight, white and male.
In most contexts, a workforce is considered diverse if it comprises a large contingent of non-white, non-male and non-heterosexual workers, but this is by no means a general rule, as evidenced by the tendency of Asians to be counted as "white" in some contexts and "non-white" in other contexts.
Many organizations, Google for example, game their diversity numbers by hiring a large contingent of "LGBTQ" workers who are white, and thus avoid the need to hire black people.
The phrase came into popular usage through its frequent appearances in Gawker, where it was used to measure the diversity of Silicon Valley firms.
Sam Biddle: "Facebook's diversity numbers are in, and they're terrible"
John Taylor: "What's wrong with them"
Sam Biddle: "They're really, really white"
John Taylor: "But it says here that the're 30% Asian. Also, isn't Facebook run by Jews?"
Sam Biddle: "yeah, Asians don't count, and Jews are white"