Showing Taken Sick Time on Paystubs

Hello!  In California employees accrue sick time but can only use a max of 24 hours a year.  The current formula in the crystal report paycheck form only allows for "what's left".  I would like to be able to show was has been taken so far so that employees get a clear look of how much they have used.  

Has anyone done this before?  I am assuming it will be a sub report.  I am fairly good at crystal reports but have not done a sub report yet.  I just wanted to see if there was someone that already worked out the best way to show this field, as it is in a different database.

Thanks!!