Learn how a running total differs from a rate of change with parcel counts: 240...

https://wiki-mixer.win/index.php/How_Do_I_Compute_the_Slope_of_a_Secant_Line_Between_Two_Points%3F

Learn how a running total differs from a rate of change with parcel counts: 240 parcels delivered by noon is a total, while 30 parcels per hour from 10 to 11 a.m. is a rate. Units and time windows make dashboard numbers easier to read.