What is check average and what moves it?

Because check is a composite, a check target can be hit in healthy and unhealthy ways. Check growth from attach and trade-up reflects customers choosing to spend more; check growth that is purely price over flat-or-down units is customers paying more for less, which tends to show up later as frequency loss.

Decomposing a check change answers the question a headline can't: of this quarter's +4% check, how much was carried price, how much was mix shift, how much was attach? That split determines whether the right response is celebration, price restraint, or a menu fix.