The DOT offers on-time performance by operating carrier for the major mainline and regional carriers in its monthly Air Travel Consumer Report. It shows performance by carrier at selected major airports (the '29 reportable'). It gives cited causes for arrival delay by carrier. The DOT also highlights chronically late flights. www.flightstats.com gives a 0-5 rating for on-time performance; it also shows a length of delay rating.

What more does one need to have an informed discussion?

https://www.transportation.gov/airco...nsumer-reports