Is the report pre-packaged and run as a batch? Or is it online/real-time? Or both?
Does the report accept parameters? Are all required or optional? Are there requirements around parameter defaults?
What are requirements for sort criteria?
What are requirements for the report formatting, column width, header, pagination, ...?
What are requirements for the column order?
Are there requirements for subsections, calculations, subtotals, grand totals, etc?
Are there requirements around performance / response time?
These are just some of the questions that may be answered by reading the relevant requirements (business, functional, technical, ...) and that may be testable as well.
Now, if you're concerned about unit level testing of the calculations, you again need to know what is required of the calculations and write cases that exercise those calcs specifically.
While testing reports, you can often run the report 1 time and actually verify/validate multiple test points.
Other than that, you'd need to be more specific about the precise problem before more info is forthcoming. [img]images/icons/smile.gif[/img]