See how running totals differ from rates of change with daily parcel...

https://shed-wiki.win/index.php/Why_Does_the_Derivative_Not_Work_on_a_Pure_Transaction_History%3F

See how running totals differ from rates of change with daily parcel deliveries. “120 parcels this week” is a total, while “20 parcels per day” is a rate. The article explains how units and time windows help you read a report correctly.