Based on this data tell me what results you would expect:

......Miles.....Gals.....Filled = Y.....MPG
......1000.......12............................... ...
......1367.......11.........Y..................... .
......1623.......10............................... ...
......1972.......14.........Y................??...
......2200.......13............................... ...
......2500.......10............................... ...
......2833.......12.........Y................??...


--
Biff
Microsoft Excel MVP


"Terry Bennett" wrote in message
...
I have a worksheet used for calculating vehicle fuel economy statistics.
The columns a

A - Date
B - Mileometer reading
C - Amount of fuel added
D - Whether tank full or not ("Y" if full / blank if not)

In column E I want to display the Miles Per Gallon (MPG) based upon the
most recent fill-up. Hence, if the tank was filled, I need to devise a
formula that refers back to when it was last full (ie; when column C last
had a "Y" entered) and then subtracts today's mileage from that in column
B when the tank was last full. If the tank was not full then column E
remains blank until next time it is full.

I can only think of using VLOOKUP for this but not quite sure how as there
will be many instances of "Y" in column C - I just need the most recent.

Any ideas?

Thanks.

Terry Bennett