What can be said about a group that cannot be said about any member of it. Statistics describe sets, never individuals.
German Statistik (the science of the state's affairs), from Neo-Latin statisticum, from Latin status (a standing, a condition); the science of counting whole populations descends from the word for a government's own condition.
What can be said about a group that cannot be said about any one of its members. Descriptions of sets, and never of the people making them up one by one.