Ah! Great question I get asked a lot, let's see if I can help.
First: pay schedules operate on a logarythmic scale, as well as rotational patterns depending on quarter, proximity to fiscal year budget projections, and divisional management vacation stacking (which I personally think is crap, but they never asked me), so before we move on to the next step you'll have to have that information in front of you. It's easier if you can create a Word spread sheet.
Second: Much of this----maybe 70%----depends on your pay rate. Say for instance your hourly $ is $27.50; that itself will determine your weekly number of hours, a number itself dependent on quarter hr. breakdowns, and as run by department budget projections. All this data is finalized, approved (or not) by the store manager, signed, zeroxed and faxed to district management, who in turn re evaluates it all and kicks it up the chain to corporate. But not before regional has a say so.
With me so far?
The final step is to count on putting in at least 90 hours per week/1st 9 weeks, of which you'll be paid for 6 of those 81. (yeah that sucks, I agree, but it's union rules and they didn't ask me about that either, hahahaha). The remaining balance will be incrementally paid to you onn a per birthday basis of your second born son, in the form of 8% per b day til his 18th year, at which time it will decrease on a yearly basis of 2.75% til his 44th b day.