Pivot Point Formula

Does anybody know how Pit Traders and other professional traders calculate pivot points for S&P500 futures? What is the actual formula they use? The reason I'm asking is because I find discrepancies among different charting programs and on-line sources. The biggest differences is for 4R/S calculations.

I primarily use Ensign 10 with the formula below that seems to work well with ES. But why are there different formulas and what is the best one to use for ES? I want to know what the Pit Traders use?

•Pivot = (High Point + Low Point + Close Point) / 3
•Range = High Point – Low Point
•4R [4th Resistance] = 2R + Range
•3R [3rd Resistance] = 1R + Range
•2R [2nd Resistance] = Pivot + Range
•1R [1st Resistance] = Pivot + (Pivot - Low)
•H [Yesterday's High]
•P [Pivot Price, i.e. Midpoint]
•L [Yesterday's Low]
•1S [1st Support] = Pivot - (High-Pivot)
•2S [2nd Support] = Pivot - Range
•3S [3rd Support] = 1S – Range
•4S [4th Support] = 2S - Range

I studied Pivots for years.
Don't worry about what the 'pit' traders use. The dollar value of contracts traded in the pit is only about 1% of the dollar value traded in the electronic Globex market.
You have to look at calcs for Pivots that are most used by electronic traders.

I have found Woodie's calcs to be the most popular.

The formulas are right here

http://www.mypivots.com/dictionary/definition/228/woodie-pivot-points

BUT, I have to point out, Don't go by the numbers in the daily notes page here because they are based on 24 hour Globex prices...that's a No-No. You have to calc the pivots based only on the RTH data. (I had come this conclusion years ago... I recently started following ShadowTrader, and they do the same thing

The Woodie's calcs (using the close of the day in place of the open for the pivot = PP = (H+L+C)/3) is the most common... I read and watch Shadow Trader, and they also use those formulas and they also only calculate the pivots based on Regular Trading Hours.

I have to take the time to point something out: having a pivot level at a price is not really the best reason to make a trade there. You have to have some other technical level in the vicinity, too, like a prior day H or L, or a VAL or a VAH. or a weekly H, L, a Weekly VAL or VAH... because there are plenty of traders out there that don't look at pivots at all...they read a chart...So, you need something more than a Pivot level, you want some other reason ...the more eyes that are focusing on a level to react and trade, the more likely you get a movement in your favor.