Numeric UDF not bringing correct data into XL Reporter

Hello everyone--

I have a UDF on the document header for A/R invoices. It is a 2-digit numeric field with valid values. There are only two possible values (25 and 50), or the field can be left blank. In XL Reporter, I have set this field to be visible as a measure-type field. However, when I include the field in a report, completely different values are shown. Records where the field is blank show it as a zero, which is fine. But records that have either 25 or 50 in the field appear on the report as completely different numbers - 900, 150, 300, and others. There is no correlation I can see between the value in the database and the value that shows up in XL Reporter, and it is not consistent from one record to another. I get the same result in the Report Designer and the Report Composer.

Can anyone help? Thanks.

Marcia