Q: Hi Richard. I need some help. I'm no excel pro! This is what I need: I want to know the average the product is being bought within Excel. eg: product X is being bought every X months

Product# Date Purchased Date Purchased Date Purchased
100.0 2007-08-22 2007-11-20 2008-04-13
602A.0 2007-06-25 2007-10-15 2008-01-05

THANKS FOR YOUR HELP. Joey


A: Good question.

If you have two dates, let's say 1/1/2008 and 2/1/2008, those days are 31 days apart. You can find this by simple subtraction. For example, if you put those values in cells A1 and B1, respectively, then you can just put this in C1:

=B1-A1

Now the result is going to say 1/31/1900, but that's OK. Just right-click on the cell and go to FORMAT CELLS and reformat that value to NUMBER, and now it's represented in the "number of days" between those two dates.

Knowing how to do that, now the rest of your problem is just mathematics... add up the total number of days, and divide by the number of sales, and you have the average sales per day (or month, just divide by 30 or 31).

I cover this topic in my Excel 232 class: /site/courselist/excel/excel232

Hope this helps