I have two worksheets.

The first worksheet is a work schedule, "Schedule2007", which includes a
"Date" column, and 12 columns for "Overtime".

Column B is the "Date" column with dates formatted as mm/dd/yyyy ranging
from row 3 through 420 (July 1 - December 31).

The "Overtime" columns are broken down as follows; AD:AF (Labeled "1st
Half") = 4 hour shifts; AG:AI (Labeled "2nd Half") = 4 hour shifts; AJ:AO
(Labeled "Full Shifts") = 8 hour shifts.

Employees enter their initials into the "Overtime" columns based on which
shifts they've worked on the corresponding dates in column B. However,
employees can enter their initials in the "overtime" columns for future dates.

My second sheet will be used to calculate ongoing overtime hours, by month,
but I do not want to include hours for dates which have not yet been worked.
For example, since today is 10/16/2007, I would like to see overtime hours to
date for October, but not those signed up for after today's date.

The second worksheet is labeled OvertimeTotalsByMonth and is formatted as
follows:

Column A = Employees (corresponding to the initials in the overtime columns
on the "Schedule2007" worksheet, such as "ABC")

Column B:H = "July", "August", "September", etc.

Column I = "Total Overtime Hours" (year-to-date by employee)

Is there a SUM formula I can use to A) reflect that the cells in the
overtime columns on the first sheet = 4 or 8 hour shifts, and B) exclude
dates that haven't occurred yet?

I'm using Excel 2003.

Sorry for the long winded question. Any help is appreciated.

Thanks,

Mike