This is a simplified version of the Dr. Neau formula, which you may read about here.
square root of the prize pool
DIVIDED BY
place finishing in + 1
Example: $30 buy in, 30 players. Points for:
1st: 15 2nd: 10 3rd: 7.5 4th: 6 5th: 5 7th: 3.75 9th: 3 14th: 2 20th: 1.42
It rewards those who do well in large tournaments (or high buy-in ones), and it goes up inversely to reward those who make it deep consistently. It's harder to go from 4th to 3rd than it is from 14th to 13th.
We do different event variations and different buy ins and play 8 events per year (count only your best 6 scores so those with perfect attendance don't dominate our year-end free roll).