Wow! I'm sure part of the reason is all vintage Macs seem to have increased in value after Steve Job's death. However, a Google search shows that's not the first time a Performa 200 has sold for a lot of money, so its value is probably also partly due to it being badged as a "Performa 200" which I think is pretty rare. I had never heard of it and had to look it up to see it's just a Classic II with a different name.