Count cells every 12th column?
 

Hello,

I am trying to come up with a formula that will help in calculating
averages in my visitor tracking spreadsheet. My spreadsheet has a lot
of visitor demographics and head count data entered by day. Across the
top, I have dates as column labels. Down the side, I have different
visitor demographic age ranges as row labels. On the lowest row, I
have a total of all the visitors in any given day.

I've already figured out the formula to count the different age groups
and genders. Now what I need is a formula to count the total visitors
per day, but end up with totals for all Mondays, Tuesdays,
Wednesdays,etc.......

Other info: We are only open Monday - Saturday, so I only have those
dates across the top.

Here is a screenshot of the spreadsheet:
http://www.flickr.com/photos/jenkob/2628527135/


My ultimate end goal is to be able to get an average number of
visitors for each day of the week. (Example: Average Saturday
visitation- 12 people)

I have tried to modify this formula which I've used to count the
totals in my gender columns, for each age row:
=SUMPRODUCT(--(MOD(COLUMN(5:5),2)=0),5:5)

But it does not work because it only counts every *other* column, and
what I need to do is count every 12th column. I tried to modify the
above as follows:
MOD(...,12)

But when I checked it, the figure was incorrect. So there must be
something wrong.

Can anyone help?

Count cells every 12th column?
 

You need an offset to account for the first non-data columns:

If your first number to use is in Column ???, use
=SUMPRODUCT(--(MOD(COLUMN(5:5)-COLUMN($???$1),12)=0),5:5)

Replace the ??? with the column letter, like this for column B:
=SUMPRODUCT(--(MOD(COLUMN(5:5)-COLUMN($B$1),12)=0),5:5)

So, to get the average, you need to count the filled in cells, so use

=SUMPRODUCT((MOD(COLUMN(5:5)-COLUMN($B$1),12)=0)*5:5)/SUMPRODUCT((MOD(COLUMN(5:5)-COLUMN($B$1),12)=0)*(5:5<"")*1)

HTH,
Bernie
MS Excel MVP


wrote in message
...
Hello,

I am trying to come up with a formula that will help in calculating
averages in my visitor tracking spreadsheet. My spreadsheet has a lot
of visitor demographics and head count data entered by day. Across the
top, I have dates as column labels. Down the side, I have different
visitor demographic age ranges as row labels. On the lowest row, I
have a total of all the visitors in any given day.

I've already figured out the formula to count the different age groups
and genders. Now what I need is a formula to count the total visitors
per day, but end up with totals for all Mondays, Tuesdays,
Wednesdays,etc.......

Other info: We are only open Monday - Saturday, so I only have those
dates across the top.

Here is a screenshot of the spreadsheet:
http://www.flickr.com/photos/jenkob/2628527135/


My ultimate end goal is to be able to get an average number of
visitors for each day of the week. (Example: Average Saturday
visitation- 12 people)

I have tried to modify this formula which I've used to count the
totals in my gender columns, for each age row:
=SUMPRODUCT(--(MOD(COLUMN(5:5),2)=0),5:5)

But it does not work because it only counts every *other* column, and
what I need to do is count every 12th column. I tried to modify the
above as follows:
MOD(...,12)

But when I checked it, the figure was incorrect. So there must be
something wrong.

Can anyone help?

Count cells every 12th column?
 

Thank you, that works!! The averages formula doesn't, but I think I
can work around that another way. (I know how many Saturdays are in a
season, so I can just do a formula based on the return result from the
total visitation per day.

Count cells every 12th column?
 

The average formula will work if the cells without values are blanks, rather than filled with
zeroes.

HTH,
Bernie
MS Excel MVP


wrote in message
...
Thank you, that works!! The averages formula doesn't, but I think I
can work around that another way. (I know how many Saturdays are in a
season, so I can just do a formula based on the return result from the
total visitation per day.