Using a Week Number as One Criterion in a Formula

by Allen Wyatt
(last updated November 16, 2019)

Dave is trying to create a SUMIFS formula that uses the year as one criterion and the week number as another criterion. This will allow him, for instance, to sum all the values from a particular week in a previous year. The week number criterion needs to be based on whatever week number the current date is within. Thus, if today is within week 3, the formula needs to include weeks 1, 2, and 3 from whatever year he specifies. Dave is sure there is a way to do this, but he can't figure out the right way to express it in SUMIFS.

Using the SUMIFS worksheet function, it is important to understand exactly what the function needs as parameters. When working with two criteria (as Dave wants to do—year and week number), the syntax of the formula based on SUMIFS would look like this:

=SUMIFS(values_to_sum, years_to_compare, year_criterion,
weeks_to_compare, week_criterion)

In Dave's description, what he has is a series of dates and a series of values related to those dates. The values_to_sum parameter is obviously from those values Dave has, but the years_to_compare and weeks_to_compare don't exist in his data. Thus, they must be created in helper columns.

Let's assume that column A contains Dave's original dates and column B contains the values associated with those dates. In column C you can create the first helper column, using this formula in cell C2:

=YEAR(A2)

This assumes that row 1 contains headings for your data columns. The formula for the second helper column is placed in cell D2:

=WEEKNUM(A2)

Copy these formulas down so that there is an associated year and week number for each date that appears in column A. With these helper columns in place, you have all the data pieces necessary to work with the SUMIFS function described earlier. What you still don't have is an indicator of which year you want to extract from the values. This is easily remedied by placing a year into cell F2. Now the requested formula would appear as follows:

=SUMIFS(B:B,C:C,F2,D:D,"<="&WEEKNUM(TODAY()))

If you compare this formula to the syntax example provided earlier, you'll note that you have the values_to_sum (B:B), the years_to_compare (C:C), the year_criterion (F2), the weeks_to_compare (D:D), and finally the week_criterion. It is this last element which needs to be explained a bit; it looks like this:

"<="&WEEKNUM(TODAY())

Since the WEEKNUM function returns whatever week number is appropriate for (in this case) today's date, it may return something like "7". Thus, the week_criterion ends up looking like this:

"<=7"

This means that SUMIFS will only consider those week numbers in the data that are less than or equal to 7.

You might wonder if you can get rid of the helper columns. You cannot do so with SUMIFS. The reason is because the function expects data ranges upon which to do its comparisons, and those data ranges are calculated as the result of formulas in columns C and D.

As a final caveat to using this formula, you should understand precisely how you want to calculate your week number. In the examples in this tip, the simplest version of the WEEKNUM function was used, both in column D and in the SUMIFS formula. There are parameters that can be used with WEEKNUM to adjust how it works. In some instances, you might want to calculate an ISO week number instead. More information on WEEKNUM and ISO week numbers can be found in these tips:

http://excelribbon.tips.net/T007804
http://excelribbon.tips.net/T007847

ExcelTips is your source for cost-effective Microsoft Excel training. This tip (12964) applies to Microsoft Excel 2007, 2010, 2013, 2016, 2019, and Excel in Office 365.

Author Bio

Allen Wyatt

With more than 50 non-fiction books and numerous magazine articles to his credit, Allen Wyatt is an internationally recognized author. He is president of Sharon Parq Associates, a computer and publishing services company. ...

MORE FROM ALLEN

Automatic Scrolling

Spend a lot of time scrolling around in your document? You might find one of Word's hidden scrolling commands to be a ...

Discover More

Embedding Fonts in a Document

Fonts are essential to getting your text to look just the way you want it to look. If you have a font that you use in a ...

Discover More

Adding Up Tops and Bottoms

When you are working with sequenced values in a list, you'll often want to take some action based on the top X or bottom ...

Discover More

Professional Development Guidance! Four world-class developers offer start-to-finish guidance for building powerful, robust, and secure applications with Excel. The authors show how to consistently make the right design decisions and make the most of Excel's powerful features. Check out Professional Excel Development today!

More ExcelTips (ribbon)

Displaying Letter Grades

Grading in schools is often done using numeric values. However, you may want to change those numeric values into letter ...

Discover More

Using the IF Worksheet Function

Programmers know that a staple of any language is the ability to create conditional statements. Excel understands this, ...

Discover More

Strange ATAN Results

You may use Excel's trigonometric functions to do some quick calculations, and suddenly notice that the results in your ...

Discover More
Subscribe

FREE SERVICE: Get tips like this every week in ExcelTips, a free productivity newsletter. Enter your address and click "Subscribe."

View most recent newsletter.

Comments

If you would like to add an image to your comment (not an avatar, but an image to help in making the point of your comment), include the characters [{fig}] in your comment text. You’ll be prompted to upload your image when you submit the comment. Maximum image size is 6Mpixels. Images larger than 600px wide or 1000px tall will be reduced. Up to three images may be included in a comment. All images are subject to review. Commenting privileges may be curtailed if inappropriate images are posted.

What is two less than 4?

There are currently no comments for this tip. (Be the first to leave your comment—just use the simple form above!)


This Site

Got a version of Excel that uses the ribbon interface (Excel 2007 or later)? This site is for you! If you use an earlier version of Excel, visit our ExcelTips site focusing on the menu interface.

Newest Tips
Subscribe

FREE SERVICE: Get tips like this every week in ExcelTips, a free productivity newsletter. Enter your address and click "Subscribe."

(Your e-mail address is not shared with anyone, ever.)

View the most recent newsletter.