This guy isn't worried

http://www.dailymail.co.uk/news/article-3663890/Billionaire-major-Brexit-donor-reveals-lost-400m-stock-market-meltdown-vote-insists-no-regrets.html

Retired & billionaire, are I think the key words. Obviously having stumped up 3.2 million pounds for the Brexit campaign he is unlikely to be expressing any regrets now.