Adding Values to Rows and Columns

The release notes for CTP3 references the ability to add values to rows and columns. But what does this really mean? Inspired by quite a few questions on this already I thought I'll try to provide a little more details on this.

In the RTM version of PowerPivot you can add multiple measures to the values area of a PivotTable, but you are not able to add measures to rows and columns. Let me add some examples to illustrate.