Payroll not adding benefits to Net Pay

Hi,

We have pay code (salary), benefits and deductions setup. Benefits are not added in Net pay calculation. Even on Microsoft video demonstration I can see the benefits are not adding to net pay. I don't see any setup option which can enable that as well. 

Below is example (assuming no tax):

Basic Pay =  $1000

Benefit = $300

Deductions = $200

GP is calculating the Net Pay to be $1000-$200 = $800 and ignoring the benefits of $300.

Pay should be $1000+$300-$200= $1100

How can I make the benefits to be added to calculation.

We are using standard HR and Payroll (not advanced Payroll or extensions etc.)

Thanks in advance.