The phrase "historic norms" refers to the average or typical behavior, actions, or conditions that have occurred in the past and continue to influence what is considered normal or expected in the present. Full definition
The typical amount of time it takes to sell a home is shrinking, and for traditional sellers is now in the range of historic norms for a balanced market. (nar.realtor)
Further, the uniqueness of each includes a unique superiority, namely, the ability to achieve what, by its own historic norms, is most important. (religion-online.org)