To be fair, this data is old. I personally know quite a few SA expats who've gone back in the last few years, pushed by UK recession and a realisation that things are not that bad back home after all. Mbeki is gone, Zuma should go next year, the sort of feared Mugabe-like regime hasn't materialised.

Yes, there has been a (white) exodus in the late 90s, but it looks like the correction might have been a one-off.