Simple PTO Accrual Spreadsheet

I've been asked to create a simple PTO accrual spreadsheet. This would be including balance PTO + accruing PTO - USED PTO. Something like this:

Balance Accruing PTO USED PTO Remaining PTO
40.00 4.62 16.00 28.62
28.62 0.00 00.00 28.62


What formula(s) would I use to make this happen?

Maybe like this?