Hello Andrew
I believe visio professional is required, not standard. From help:
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Visual reports enable you to view your project's data in PivotTable
(PivotTable: An interactive table that summarizes, or crosstabulates,
large amounts of data. You can rotate its rows and columns to see
different summaries of the source data, filter the data by displaying
different pages, or display details.) reports in Microsoft Office
Excel, and PivotDiagram views in Microsoft Office Visio Professional
2007.
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I hope this helps. Let us know how you get along.
Julie
Project MVP
Visit
http://project.mvps.org/ for the FAQs and additional information
about Microsoft Project