Spreadsheets: Mission Impossible Completed with PowerPivot

Kelly W. wins an autographed copy of PowerPivot for the Data Analyst from CFO and MrExcel for submitting this week's question: "I am utilizing Pivot Tables to analyze some large amounts of data on purchases. Each row of my pivot table is the ID # of a product so I can clearly see what products are purchased the most frequently and for the most dollars. I also have two columns for "Max of Unit Price" and "Min of Unit Price." I would like to add a third column "Price Range" that is simply the difference of the two columns already in the Pivot Table. It appears the calculated field option will not work. Every row ends up with a value of $0. I have searched the Internet to find a solution. Unfortunately, while I have found others with the same question I have yet to find a resolution. Any help would be greatly appreciated!"