Learn to tell a running total from a rate of change using parcel deliveries as...

https://www.mediafire.com/file/wgtscej188dt036/pdf-11118-32695.pdf/file

Learn to tell a running total from a rate of change using parcel deliveries as an example. A dashboard might show 120 parcels shipped so far, or 15 parcels per hour. The time window and units tell you what each number actually means.