HogansHero said: "As to the original query, there is not and should not be a correlation. Would you want actors to work for less because a show is deeply discounting and/or not selling?"
I don think that's what the OP meant. I took it to mean are the increases in list price (over the last few years) being caused, at least in part, by increases in salaries, not that the price paid for a particular performance reflects any alteration of the actors' pay for that performance.
Or, to put it another way, are the actors, musicians and crew sharing in the increases in grosses that come from the higher ticket prices, or is it all going to the producers?
Truthfully, I don't know. Prices in any field don't necessarily reflect the costs to produce a product, but are as much a matter of what the market will bear. That is, they charge as much as they can and still have the tickets sell; discounts represent a corrective action when the producers tried to charge too much and couldn't sell the tickets at full price. If discounts get too steep and sales are not covering running costs, the show is probably closing soon.
As such, rising ticket prices don't necessarily reflect an increase in costs for the actors/musicians/crews' salaries, though it may contribute, as the producers do need to cover costs, and salaries are a major cost. But without exact knowledge of the finances of any show, we don't know the breakdown enough to do anything more than speculate.