That's interesting to know.
It's also worth noting that technically Pitt isn't a public school. It's actually a private school "with state support." Which means that it's a private school that, a long time ago, made agreements with the commonwealth of PA b/c Pittsburgh was one of the biggest cities in the country (at the time) and didn't have a good public university. This is why, BTW, Temple is cheaper than Pitt and Pitt's undergraduate is a bit more expensive (around 10k) than most public colleges.
But it's relevant b/c Pitt isn't required to follow any requirement or guideline for how many state residents they must admit -- as many other public schools are (wisconsin, iowa, texas, virginia, tennessee -- the list goes on).