Don’t think I’ve seen these stats on here before? The source data was extracted from QuakeInjector’s database.xml. Top level file elements in the db were counted as releases and startmap elements were counted as maps, e.g. a map jam with ten maps was counted as one release and ten maps. File elements without a startmap element were counted as one release and one map. The year was read from the date elements.
Interesting to see how active the comunity has gotten in the last few years! (Anyone remember when quake was re-released on steam and gog?)