I meant actual times, the MUTCD only says you must use "engineering practices" in determining the interval. The ITE equation was included in my link -- however it optimizes for reduced red-light violations, so it's no wonder it's not used in these cases.

Huh, it's interesting that there's actually an engineering standard for yellow light times that local governments don't seem to acknowledge. I've always been annoyed at the dangerously short yellow lights around here (Denver), compared to the rest of the country. (I think they were short even before we had red light cameras.) When I'm traveling in other states, I often find myself automatically hitting the brakes when I see yellow, only to sit at the yellow light for a few seconds. :/