Here's my Record Selection Formula -
{master.DATE} in Date (ToNumber ({?ReportYr}),{?ReportMo},01) to Date (ToNumber ({?ReportYr}),{?ReportMo},31)

The error I get is parameter must be numeric. It's talking about the {?ReportMo} parameter. When I change that parameter to a number such as 08 for August, the error goes away, but I want to have user be able to enter the Mo and Year for the report as a parameter. What am I doing wrong? Thanks very much.