[AccessD] Changing table values via code

Hi everybody...long time since I've asked a question here, but I find
myself needing help again.

I am working on a db for a payroll dept. One of the things I need to do
for them is to keep a running total for time off. Basically each
employee will have a record in a table with fields for vacation,
personal, sick, etc., and I need to do two things with these numbers. I
need to add to these totals at the beginning of each years, as they earn
more time. And, I need to subtract from these totals as they use their
time. So, when a payroll clerk enters a value of 7 hrs vacation for an
employee on a given day, I need to subtract seven from their total
vacation hours.

Both of these will be done via code, at the time of the change, but I
have never done this before. I would appreciate any direction you could
offer.

Thank you


John W Clark