This is similar to the concepts of inflation and deflation except that escalation is specific to an item or class of items (not as general in nature), it is often not primarily driven by changes in the money supply, and it tends to be less sustained.
While escalation includes general inflation related to the money supply, it is also driven by changes in technology, practices, and particularly supply-demand imbalances that are specific to a good or service in a given economy.
Over long periods of time, as market supply and demand imbalances are corrected, escalation will tend to more-or-less equal inflation unless there are sustained technology or efficiency changes in a market.
Escalation is usually calculated by examining the changes in price index measures for a good or service.
Unfortunately, because escalation (unlike inflation) may occur in a micro-market, and it may be hard to measure with surveys, indices can be difficult to find.