Calculating Rakeback in PT

What is the best way to figure out our amount of rakeback party style in pokertracker? I had heard that taking the total rake from the general info tab and multiplaying that by your percent rakeback was close enough, but I have found that to be way too short.

I then read ZBTHorton's method in this thread about multiplying amount of raked hands by average raked divided by average players multiplied by rakeback percent and thought this was more realistic.

Then I remembered PokerGrapher had a rakeback feature built in it. Does this add it all up exactly as party does? In that thread there was some SQL coding, but I have no idea how to use that.

I found out that the PT's general tab was less than ZBTHorton's method which was less than PokerGrapher's method. Which is the most accurate? I play 6max limit games almost exclusively if that makes any difference.

I have the program if you want it. PM me.

For anyone else reading this thread, I found out that Pokergrapher's rakeback calculator was within a few cents of the program that he gave me.