A running total tells you how much has piled up; a rate of change tells you how...

https://www.bookmarking-presto.win/totals-add-up-what-has-happened-rates-show-how-fast-it-happens-for-parcels

A running total tells you how much has piled up; a rate of change tells you how fast it’s moving. Use parcel counts per hour or rainfall in inches per day to see why units and time windows matter when reading a chart at work.