Microsoft Excel 2007: The Countif Function
The COUNTIF function is used to count the number of cells in a given range which satisfy a condition. COUNTIFS does the same. However, here, we can specify multiple criteria. For example, let’s say we have a worksheet containing four columns: the date, the number of phone calls received, the number of complaints and the percentage of calls which were actually complaints.
We now want to create a summary worksheet to calculate the number of days where the percentage of calls that were complaints is, firstly, under 5%; secondly, between five and 10% and, thirdly, over 10%.
To work out those days where we have fewer than 5% or more than 10%, we can use COUNTIF function because we are dealing with a simple condition: less than 5% or greater than 10%. However, to calculate the number of days where we had between 5% and 10%, we will need multiple criteria; firstly, greater than or equal to five and, secondly, less than or equal to 10. We will therefore need the COUNTIFS function.
When creating formulas, it is always useful to give names to the ranges of cells are you are referencing. To allow Excel create the names for you automatically, select all of your data, including the column headings then, in the Formulas Tab of the Excel Ribbon, click on Create from Selection. Switch on the option ”Create names from values in the Top Row” and click OK. Let’s assume that the heading at the top of the fourth column (the one containing the percentage of calls which were actually complaints) is ”Percentage”, this would be the name that we would use in our COUNTIF formulas.
Next, we can switch to the Summary worksheet and click in the cell where we want to calculate the total number of days where less than 5% of our calls were complaints. Here we would enter the formula =COUNTIF(Percentage,”<5”). Notice that, when using COUNTIF and COUNTIFS, all criteria must be surrounded by quotation marks.
In exactly the same way, to calculate the total number of days where more than 10% of our calls were complaints, we would use the formula =COUNTIF(Percentage,”>10”).
Finally, to calculate the total number of days where between 5 and 10% of our calls were complaints, we would use the formula =COUNTIFS(Percentage,”>=5”,Percentage,”<=10”). The COUNTIFS function allows you to repeat the two arguments used with the COUNTIF function (criteria range and criteria) up to 127 times. Thus, in our example, criteria range 1 is Percentage; criteria 1 is ”>=5”; criteria range 2 is also Percentage; and criteria 2 is ”<=10”.
The writer of this article is a developer and trainer with On-SiteTrainingCourses.Com, an independent computer training company offering Microsoft Excel Classes at their central London training centre.