A running total adds up what has come in, while a rate shows how fast it comes...

https://www.strobe-bookmarks.win/running-totals-show-what-has-piled-up-rates-of-change-show-how-fast-it-adds

A running total adds up what has come in, while a rate shows how fast it comes in. Use parcel counts to see why 20 parcels by noon differs from 5 parcels per hour, and why units and time windows matter when you read a work chart.