MFP excercise Stationary Bike MPH?

I have been doing searches in this forum last night and this morning, trying to figure out exactly the same thing. Some people say moderate is 12-14 mph but the answers seem to vary all over the place. Some people says it depends on how much exertion it is for you as an individual. A very helpful article, to me, was quoted in this post:

http://www.myfitnesspal.com/topics/show/563536-intensity-level-of-a-stationairy-bike?hl=stationary+bike+moderate+mph#posts-7960737

I am doing 14-15 mph and counting it as moderate. Wish I could give a better answer.