Power Pivot, commonly referred to as the Data Model is an Excel add-in that helps you to create normal Pivot reports that draw data from a variety of sources. It allows you to extend Excel capabilities in two ways: (1) You can connect to multiple data sources, create relationships and report as one, and (2) You get access to powerful formulas built on a language called DAX (Data Analysis Expressions) making calculations such as YTD and prior year comparisons very easy.

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