See why a running total of parcels delivered is not the same as a delivery...

https://www.easybookmarkings.win/compare-a-running-total-of-parcels-received-with-the-rate-arriving-per-hour

See why a running total of parcels delivered is not the same as a delivery rate. One counts parcels over a time window; the other measures parcels per hour. A warehouse example shows how units and time windows change what a chart tells you.