technically, just a little over 2 years. the majority of these gains were over the last 6 months or so though, after I read Reminiscences of a Stock Operator and realized just how rigged everything is and always was was when it finally clicked for me and I felt comfortable enough trading to quit my job.
key rule differences between the US markets and others around the world allow for blatant price manipulation (rules that pretty much every country except the US fixed, after 2000/2008), the more you read up on the history and fundamental mechanisms of the markets the more clear it is that these rule differences exist specifically so the US markets can function more like a casino than a market, to be "exciting".
always figured the game was rigged, but didn't appreciate just how rigged before reading that book. paradoxically, the whole thing being rigged makes it easier to make as it's no longer a game of chance...it's a game of identifying whose going to fuck over who, and positioning yourself between them to profit off of either side winning