If the hours are in row 3 and the data extends through column AZ:
=sumproduct(--($A$1:$AZ$1="Jan"),($A$3:$AZ$3))
A different approach would be to include a row with the start date (or end
date, whichever you'r using to assign a week to a particular month), and then
use two sumif functions. Ex if the date is in row 3 and the hours still in
row 4, then something like =sumif($3:$3,"=" & date(2006,1,1),$4:$4) -
sumif($3:$3,"=" & date(2006,2,1),$4:$4). The first part adds all the hours
in weeks beginning 1/1/06 or later; the second part subtracts all the hours
in weeks beginning 2/1/06 or later. What's left is only the hours from weeks
beginning in January.

"luvthavodka" wrote:

I have a spreadsheet that records information weekly. I'm looking to set up
another spreadsheet that takes the information from this one and inputs
themothly totals/averages (depending on the data).

My first spreadsheet has Row 1 showing Jan Jan Jan Jan Feb Feb Feb Feb Feb
Mar etc (the number of time the month shows depends on the number of weeks in
that month).

Row 2 has the week number ie 1 2 3 4 5 6 7 8 etc.

Column A has various headings (the first being number of hours)

I want my new spreadsheet to count the sum of hours relating to the month of
Jan. I'm assuming for this I need to use HLOOKUP as the data is stored
horizontally. So far I can only get HLOOKUP to return the data from the first
time it sees Jan in the row.

Can anyone assist me with a formula using SUMPRODUCT combined with HLOOKUP
to calculate all of the times it sees Jan?

Any other ideas would also be greatly apreciated!!!