Calculating Pay

[Mike]

I have a Form called TimeCard and a Subform called
WorkHours. The subform is used to enter jobs, hours, and
pieces that an employee performs during the work day. Each
job is assigned a Company_No to identify the customer the
work is being done for. There are 3 ways an employee can
be paid: Piece Work, Hourly Wage and Average Wage. The
Company_No determines which Rate is used.
Example:

If Company_No = "01" Then payrate = Average Wage
If Company_No = "02" to "79" Then pay rate = Piece Work
If Company_No = "C1" to "M9" Then pay rate = Hourly Wage

The RecordSource for the subform is a query called
WorkHours which gets it's data from 2 tables, JobCodes and
TimeCards. When a JobCode is entered in the subform, the
Company is filled in automatically. The 3 ways of
calculating pay is in the JobCode Table. The fields are:

JobCode
Description
WageBase (Hourly rate)
Rate (Piece rate)
Company_No

The AverageWage is taken from the Employee table.

I need to know how to calculate pay based on the
Company_No. I thought there might be a way to attach code
to the Pay field in the subform, but don't know how.

Thanks for any help!