Gottlieb replay games shipped with one counter for total plays. Add-a-ball games shipped with NO counter. Test games might be different.

For the replay models, it was assumed that the operator would count coins to determine the number of paid games, while the counter would count total games played. Thus, you would have the two variables needed to calculate the replay percentage. However, for variable pricing, this only works if the coin denominations can be used to determine what price was paid. For example, if the pricing is one game for a dime and three for a quarter, then you count the number of quarters, multiply by three, then add in the number of dimes to get the total paid plays. When the pricing is one game for a quarter and three games for two quarters, you would need an extra meter to distinguish the two pricing options.

Do you have evidence of what the play pricing was when the game was originally operated?
.................David Marston