Easiest way to find the last row number in the most primitive situation is to
count nonblank cells in the range where the data is going to be, column A in
this case. Put this in a cell in any column other than A (otherwise you get
a circular reference error).
=COUNTA(A:A)
By " the most primitive situation " I mean one where there aren't any blank
cells in the middle of a list. COUNTA() counts non-blank cells.

Look at grouping and subtotal functions to assist with your averages issues.

"Dallman Ross" wrote:

Hi,

I'm interested in averaging some column ranges. I'm stuck
because I don't see an easy way to find the row number of the
last row with data in it.

For example, assume some stock data:

A B C D E F
Date Open Hi Lo Close Vol
1 4/23 20.00 20.41 19.82 19.89 1,000,000
2 4/28 19.81 21.01 19.81 20.92 1,111,111
3 4/30 21.11 21.81 21.11 21.80 1,010,101
4 5/13 24.14 24.26 24.01 24.02 2,322,122
5 5/19 22.22 23.33 22.13 22.51 1,732,222

And so on. Not every date is filled. (Only trading
days, but let's not even assume that much.) So
suppose I want to average May's data for the close.
I need to know that the data ends on Row 5. Then
I need to average only entries that show May in Col. A.
can someone help me do this?

I have a feeling some will say it's not necessary to find the
bottom row number. But I still would like to know how to find it.
Oh, and I will also want to find, e.g., averages for the last year,
3 months, etc., as well.

Thanks,
dman