Greetings! I am trying to use Tableau to automate a variance analysis calculation. In the attached example, I have raw data with sales quantities and sales amounts from two different periods: 2009 and 2010. The measure fields are the same and what differentiate one type of record to the other (i.e., 2009 vs 2010) is a dimension called "Year Name". The variance analysis is trying to explain how much of the difference in revenues from one year to another is due to a) price variation or b) volume variation. The formula to calculate a) is as follows: Variance due to price = (Quantities current year - Quantities previous year) * unit price for current year The formula to calculate b) is as follows: Variance due to unit price = (Unit Price current year - unit price previous year)*Quantities for previous year For example: Revenues in 2010 are $ 3500 (200 units sold) and revenues in 2009 were $ 2500 (180 units sold) Total Variance: 3500 - 2500 = 1000 ->Broken down as follows Variance due to price = (200 - 180)*(3500/200) = $350 Variance due to quantities = [(3500/200)-(2500/180)] * 180 = $650 In order to address each step of the calculation I created some calculated fields: Unit Price: sum([Revenues])/sum([Quantities]) Delta Qtty: [Quantities] -=> and added a table calculation that calculates the difference from previous The calculation for "Unit Price" and "Delta Qtty" are correctly displayed in the screen. I tried to create another calculated field to execute "Unit Price" * "Delta Qtty" but get the error message stating I can not mix aggregate and non aggregate calculated fields. I sense that there may be a more elegant and functional way to perform this calculation but can not come up with a solution that wouldn't require manipulation of the raw data - which would be done either in Excel or MsAccess. Any thoughts or ideas would be greatly appreciated. Thanks, Edson (DuPont)