This article shows how a running total differs from a rate of change, using...

https://stephensnicejournal.almoheet-travel.com/how-do-i-explain-total-accumulated-without-sounding-technical

This article shows how a running total differs from a rate of change, using parcels as an example. See how units like parcels and parcels per hour, plus the time window you choose, help you read a shipping chart and avoid mixing a total with a pace.