Kelly wants to display a Delta in a Pivot Table. Unfortunately, Calculated Fields in a Pivot Table look at each individual row, so the MAX(B2)-MIN(B2) will always be zero.
In this video, a DAX Measure solves the problem. But to unlock DAX, you need to choose Add This Data To The Data Model.

Table of Contents
(0:00) Need Max minus Min in pivot table
(0:31) MIN and MAX are easy
(0:51) Calculated Field fails
(1:51) Add to Data Model
(2:51) New Measure
(4:25) Wrap-up