Hi

I am trying to calculate depreciation in my Excel spreadsheet. The
depreciation is over 60 months, so for a $6,000 item, the formula is
=$6,000/60 = $100

The problem I am encountering is making that calculation stop after 60
months. So in month 61, the cell reads $0, instead of $100. Is there anyway
in Excel to 'time limit' the effectiveness of a cell's formula?

To make it even more complicated, I will have ongoing items for
depreciation, so I will need to add new items to the formula, while
simultaneously letting existing items expire, as above.

It's pretty hard to explain, so I imagine it will be pretty hard to solve,
but I would certainly appreciate any advice.

Cheers,
Link.