Assuming you have no other numerical only entries (this would include dates)
in Column G except for your mileage notations, and assuming you have headers
in Row 1, put this formula in H3 and copy down as far as you want...

=IF(ISNUMBER(G3),G3-MAX($G$2:$G2),"")

Rick


"Mike Rogers" <Mike060349@NoxSpamxAOLDOTcom wrote in message
...
I have a receipt sheet set up where I log every receipt from every store I
buy anything from. I have a €œComments€� column to make note of what item
was
used for. In this €œComments€� column, I also log my mileage after I buy
gas.
I can then use the information to determine my gas mileage after each
purchase. I need a formula in Column H to look back up Column G to the
last
number to subtract it from my current mileage. Without a formula here I
have
to look back up the column, find the last number, and enter the formula:
=€�Miles last time I bought gas€�-€�Todays mileage€�. The number of rows
between each mileage entry can very depending on how many other receipts I
have accumulated. I know that =LOOKUP(9.99999999999999E+307,G:G) will
look
down a column and find the last number, can I use something similar to
look
back up the column?

Mike Rogers