These results re just pure luck, there s no way anyone ll see 1000 BTC lost by one single person again as it happened on Betking a few months ago. So these graphs represent PURE LUCK and nothing more.
gambling is always pure luck so investing in a gambling site (against the gamblers) is also pure luck. that is an obvious enough fact that everybody knows. but that doesn't mean you can not make profit in the long run. the only thing that you should do is to find a good site which is both popular and fair and then invest what you can afford to lose.