First of all, Merry Christmas to everyone

I´ll Try to explain my problem with an example.

I use this simple formula down the column E to solve my problem (TEMPORARILY):

E10 =IF(D10-D$1=245;"OIL CHANGE";"")

After condition met i have to change that formula manually.
Assuming that D19-D1=249, I will have to insert
in cell E20 =IF(D20-D$19=245;"OIL CHANGE";"")

So, AFTER each oil change, i need to CHANGE the locked cell. I guess i need
a macro for this one, but then again maybe not :)

Thanks everyone