That's net additional.
Great news!
The suburban Philadelphia Catholic schools are bursting at the seams. New schools are opening. These are areas with reputable public schools, and yet the parents are choosing to send their kids to Catholic schools. I think some of the folks here on FR need to get their heads out of the sand and take a look at these new lay run parochial schools. By and large, I think they would be surprised and pleased with what they find.