JimH wrote:

I don't understand where the 21 games of pins come from.

The cushion system is basically to help deter sandbaggers.

When you start the league, You begin with 21 (or some other number of) games bowled with a pin count of 4200 (200 average). (You didn't actually bowl them though)

Week one you bowl a 500 so your new count is 4700 pins and 24 games = avg. of 195

Week two you bowl a 750, pin count is now 5450 for 27 games = avg of 201

Just keep adding on until you get 21 games actual and drop the 21 games and 4200 pins.

Then You would use your actual 21 game average.

The BLS league software has this option it's called "Cushion Average"

I don't know all the in's and out's of how it works, I personally have never bowled on a league that used it.

Heres from the BLS manual explains better:

Cushioned averages (Non-Standard option)

If the league bylaws indicate that there is a cushioned average in effect, select this option. There are two possible ways for BLS-2005 to calculate cushioned averages. There is the normal method and a declining cushion option.

1. If a bowler has a 150 book average and the league has a 21 game cushioned average the math goes as follows.

Average = Pins/Games

(Pins and Games reflect what has been bowled so far and numbers reflect 3 games bowled a night.)

((150 X 21) + Pins )/(21 +Games) = Cushioned average

This means that the number of pins and games bowled is simply artificially inflated to cushion a change in the average until 21 games is reached then the extra pins and games are dropped.2. The declining cushion option works a little differently and yields slightly different results, often differing by a couple pins. With this method the average is cushioned less as the 9 game limit is attained.

Assume the bowler bowls 3 games of 125 pins each night:

Week 1 average=Book Average

Week 2 average=((150 X 6) +375)/(6+3)=141

Week 3 average=((150 X 3) +750)/(3+6)=133

Week 4 average=(Pins)/(Games)=(1125/9)=125