I know only this one particular case, sorry for the exageration. However thousands of (nameless) millionaires have left france in these past years (according to http://www.lalsace.fr/actualite/2017/04/11/de-plus-en-plus-d...) it was 12000 in 2016, 10000 in 2015 and 6000 in 2014. Not a very good development.