Sorry about the confusion. Here's that original excerpt that I put in the
OP, but let's just look at it as if it was the total set:

TimeID Num1 Num2
1 4 4
2 5 4
3 6 2
4 5 3
5 3 3
6 4 4
7 4 3
8 6 2
------------------------------
9 5 4


In Num1, there are 4 distinct values: 3,4,5,6.

The most recent of each of these values have matching Num2 values of 3,3,3,2
respectively (don't take into account the most recent entry).

The most recent value of Num2-1 = 3. Therefore, summing the 3s up that were
found before would equal 9, which is the number I really want.

The other option I was considering is somehow counting up the most recent
values in Num1 that have Num2-1 and then multiplying them by Num2-1...

Like I said originally, I'm not holding my breath here. :)


"JP" wrote:

By "most recent" do you mean the last entry in each column?

If the TimeID column will not have any blanks, this formula will tell
you the last entry in the column:

=INDEX($A:$A,COUNTA($A:$A),1)

Can you provide an example of points 2 and 3?


On Dec 20, 2:22 pm, Rothman wrote:
This solution is sort of like a first step, which is one step closer than I
was.

There are currently 24 distinct values in my Num1 column. The formula in
that link only finds the most recent value for one of those values. Is there
someway to alter the formula to where Excel can handle multiple recent values
in one fell swoop (i.e. match up those recent values with the most recent
value in Num2-1? Maybe there's someway to count them (the most recent,
unique values in Num1 that have correlating values in Num2 which match the
most recent Num2-1) up and then multiply by the most recent value in Num2?

Thanks again for your and anyone else's help.