I want to get the average time between StartTime and EndTime in VBA or in a calculated control. Then get an average for many records.
I am using Access to build controls on a form that will show the average in the form-footer so that when a user changes the form filter the [AvgTimeOnSite] control will add up the [TimeOnSite] controls from above record sets and display an average of minutes that each driver spends at a particular plant when making deliveries.

I am looking to get the average time in minutes that a delivery drivers spend at a particular plant getting loaded or unloaded.