The perfect trading system?

Hi,

After spending years and tens of thousands of dollars, I've finally created a mathematical model that perfectly predicts the past. Boy, am I gonna be rich!!!

[ Later ... ]

Crud, it doesn't predict the future, I lost all my trading capital!

P.S. This message is a joke, a parody of what some professionals actually do.

P.P.S. I'm only posting it because I'm in a bad mood.

Hope it was useful or interesting.

Best,

- Boyd