I have a dataset with a bunch of categories, dates and amounts I am using a Matrix to rollup the amounts for each category Now I need to calculate the StdDev but based on the aggregate category amounts, not over the entire 'leaf' population What is the best way to go about it? Javier Guillen http://www.msbicentral.com/Blogs/JavierGuillen.aspx

Hi Javier, Try to use the subreport to cacluate the stddev value for each member in each category, and then reference this value using subreport. If you can upgrade to SSRS 2008 R2, the nested aggregate will be allowed in reporting services. thanks, Jerry

Interesting. Thanks Jerry I ended up doing the first level aggregate on the MDX query, and the StDevP in SSRS Glad to hear that SSRS 2008 R2 handles nested aggregates!! Javier Guillen http://www.msbicentral.com/Blogs/JavierGuillen.aspx