how to add a value based on a date change in Excel?

[Guest]

I am trying to add a value to another on the first of the month. It is a
repeating condition based on the first of the month. Thanks for your help!

 

[Guest]

Do you want to add the same amount on the first of every month?

If, for instance you want to add the amount in cell B1 every first of the
month from October 2006

=DATEDIF(DATE(2006,10,1),TODAY(),"m")*B1+B1

 

[Guest]

Yes, I am trying to add the same amount every month to a value. Can I ask it
to add another cell if the date is the first of the month?

EX: I have 200 hours of vac, accuring 12 hours a month on the first of
every month. If I place the cell with the total accured next to the amount
accured each month so it updates the first.