Just saw this in a download of an SNCF altas and thought I’d share it. Makes for an interesting comparison to say Metra, LIRR, NJ Transit or MNRR. This map shows Translilien average number of trains each day on each line out of Paris. Note this excludes TGVs or Regional trains. Just suburban commuter trains.
Note some of these lines are handling 2x the busiest NY lines and 10x Metra. Whew!