Running totals show what has piled up, while rates show how fast it changes....

https://www.unitedbookmarkings.win/see-how-running-totals-differ-from-rates-of-change-with-parcel-counts-and

Running totals show what has piled up, while rates show how fast it changes. Use parcels and rainfall to see why units and time windows matter: parcels by noon differs from parcels per hour, just as daily inches differs from inches per hour