Which would make it right around $100M a month... I'm not sure her 'exact' 1 year amount, but it WAS over $1B...
She is a 'daytrader' and has figured out a way either by watching stocks, etc., with a spreadsheet, keeping an eye on things, or having just the plain 'wits' to make the trades work that she does.
She's been here a long time (her current port is over $13B) so she's been able to pull it off. Having been here 10+ years myself, I can tell you that it is ALL legit trading she does, and she's even posted some tips & helps before on the Players Board to help others, and give some advice from time to time.
I'm sure HSX has insured that those who are in the LTD Boards, their ports are watched and HSX has worked to insure that no one is manipulating stocks, and if they are found to have cheated, they are either fined by 25% of their port value, or in some cases, HSX has banned them from the game...
It can be done...but wow...like you, I'm in awe of people who do it! I just don't have the time, myself!