Please Note: This article is written for users of the following Microsoft Excel versions: 2007, 2010, and 2013. If you are using an earlier version (Excel 2003 or earlier), this tip may not work for you. For a version of this tip written specifically for earlier versions of Excel, click here: Counting Groupings Below a Threshold.

Counting Groupings Below a Threshold

Written by Allen Wyatt (last updated July 12, 2022)
This tip applies to Excel 2007, 2010, and 2013


2

Ronald imports a number of signal-level measurements as a series of values into Excel. He needs to count how many consecutive groups of values exist in this series which fall below a certain threshold. For example, he may have the following measurements:

27, 22, 22, 30, 32, 18, 22, 23, 28, 39, 24, 27, 35, 25, 21

If he wants to know the number of groupings where the members of those groupings were under 26, the answer would be 4. Note that this is the groupings of consecutive values below 26, not the number of individual values below 26. Thus, in this case, the four groupings would be shown by the brackets in the following:

27, [22, 22], 30, 32, [18, 22, 23], 28, 39, [24], 27, 35, [25, 21]

Ronald is wondering what sort of formula he can use to figure out the number of groupings that fall below some arbitrary threshold he might specify.

There are actually several different ways you can approach this. The first is to use a "results column" that essentially notes changes in threshold and sequence grouping. For instance, if you had the above values in column A of a worksheet (starting at cell A2) and the threshold value in cell E1, then you could use the following formula in every cell to the right of a value in column A:

=IF(A2>=$E$1,B1,IF(A1<$E$1,B1,B1+1))

The formula keeps a running sum of the groups below the threshold. The max (or last value) of column B provides the total number of groups below the threshold. The formula checks to see whether the value immediately to the left, in column A, is above or below the threshold. If it's above, or if not and the previous value in column A was also below, then it doesn't increment the running sum. Otherwise, it does increment because a new grouping is starting.

A related way of doing the count is to use this formula in column B, instead:

=IF(A2>=$E$1,0,IF(A1<$E$1,0,1))

This results in column B containing a series of 0 or 1 values. The only time that a 1 value occurs is at the start of a series that is below the threshold. This makes it easy to sum all the values in column B, which provides the count of groupings.

If you don't want to use the results column, you can use an array formula to figure out the count. The following formula assumes, again, that the values to be analyzed are in column A, beginning at A2, and that the threshold value is in cell E1. Remember, as well, that array formulas are entered by pressing Ctrl+Shift+Enter.

=SUM(IF((A2:A16<$E$1)*((A2:A16<$E$1)*1<>((A1:A15<$E$1)*ISNUMBER(A1:A15))),1))

The formula basically does what the previous results-column formula did (determines a 0 or 1 based on whether a below-threshold grouping is starting) and then sums those values.

Of course, if you do these types of comparisons a lot, you may want to develop your own user-defined function (a macro) to figure the count of groupings for you. The following is an example of such a function.

Function CountGroups(ByVal MyRange As Range, Threshold As Single)
    Dim Cell As Range
    Dim bInGroup As Boolean
    Dim iCount As Integer

    Application.Volatile
    iCount = 0
    bInGroup = False
    For Each Cell In MyRange
        If Application.IsNumber(Cell) Then
            If Cell < Threshold Then 'Less than the threshold?
                If Not bInGroup Then  'Only count if starting new group
                    iCount = iCount + 1
                    bInGroup = True     'Mark as being in group
                End If
            Else
                bInGroup = False        'No longer in a group
            End If
        End If
    Next
    CountGroups = iCount
End Function

The function looks through each cell in a range and calculates if it is the start of a new below-threshold group or not. You use the function by using a formula such as the following in your worksheet:

=CountGroups(A2:A16,E1)

Note:

If you would like to know how to use the macros described on this page (or on any other page on the ExcelTips sites), I've prepared a special page that includes helpful information. Click here to open that special page in a new browser tab.

ExcelTips is your source for cost-effective Microsoft Excel training. This tip (8888) applies to Microsoft Excel 2007, 2010, and 2013. You can find a version of this tip for the older menu interface of Excel here: Counting Groupings Below a Threshold.

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

Selecting a Field

Do you need to select a field? It is as simple as selecting a single character, as this tip explains.

Discover More

Preventing a Frame when Converting a Table to Text

Tables, in Word, can either be inline with the rest of your text or the text can wrap around the table. If you have ...

Discover More

Maintaining Word Formatting on Differing Systems

When you open a document on a system other than your own, it is very possible that the document will look different than ...

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)

Extracting Street Numbers from an Address

Want to know how to move pieces of information contained in one cell into individual cells? This option exists if using ...

Discover More

Grabbing the Second-to-Last Value in a Column

Need to get at the next-to-last value in a column, regardless of how many cells are used within that column? This tip ...

Discover More

Determining a Zodiac Sign from a Birthdate

If you want to find out the Zodiac sign for a birthdate, there are a number of ways you can do it. This tip provides ...

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}] (all 7 characters, in the sequence shown) 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 2 + 8?

2018-12-10 18:11:15

Yvan Loranger

The array formula is good but the 2 preceding formulae come 1 short if the sequence begins with a number below the threshold; ie the formulae indicate 3 instead of 4 groups.


2015-11-25 16:17:39

Tom Watkins

I have just read about this tip in your book, "Amazing Array Formulas", and attempted to set up this scenario in Excel myself to experiment.
All went as you published until I entered 28 as the arbitrary threshold in cell E1.
So I see that to make this method work, the first number in the series (27 in this case) must be above the threshold that I want to measure against.

Now to go on and read the part about using arrays :-).


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.