There are many situations where it’s useful to calculate an average. For example,

• What is the average height of pupils in a class?
• What is the average monthly electricity bill over the course of a year?
• What is the average amount of sick days taken by employees? By Department? By Men, By Women?

Of course there are situations where it is not useful. For example (and I don’t mean to be rude)

• On average we all have one boob and one testicle

And don’t you think it’s odd that

• 80% of drivers consider themselves better than average!

How does that work? We can’t all be right, can we!

The 3 ways to calculate an average value

You may remember from your maths lessons at school that there are 3 types of average: MEDIAN, MODE and MEAN.

• To work out the MEDIAN, Excel sorts your data values into order (behind the scenes), then selects the middle value.
• To work out the MODE, Excel sorts your data values into order (behind the scenes), then selects the value that occurs the most frequently.
• To calculate the MEAN, Excel totals all the data values (behind the scenes), then divides the answer by the number of data values in the list.

How to calculate a MEAN AVERAGE in Excel

The simplest and most common way to calculate the average value for a set of numbers is to use Excel’s AVERAGE function. This function uses the MEAN method which totals the data then divides the answer by the number of values.

The structure of the AVERAGE function is

=AVERAGE(number1,number2 …)

For example:

=AVERAGE(A1,A2,A3)

or

=AVERAGE(A1:A11)

This function totals all items within the brackets then divides by the number of items. It can be selected from the AutoSum drop down menu, or by typing it directly into the cell.

If you have values in cells A1 to A11.

To use the AutoSum tool to calculate the average:

1. Select the 11 cells.
2. Click the drop-down arrow on the AutoSum icon.
3. Choose AVERAGE from the list.

Or if you want to write the formula manually:

1. Select a blank cell that will contain the calculated average.
2. Type ‘=AVERAGE(’. You cannot use AVG or any other shortened version of AVERAGE.
3. With your mouse, select cells A1 to A11.
4. Type the closing bracket.
5. Press Enter.

Using either technique you should end up with

=AVERAGE(A1:A11)

How to calculate the MEDIAN value in Excel

The second method is to use Excel’s MEDIAN function. This function looks at the sorted sequence of data (behind the scenes) then selects the middle value.

The structure of the MEDIAN function is

=MEDIAN (number1, number 2 …)

For example:

=MEDIAN(A1:A11)

How to calculate the MODE value in Excel

The third and final method is to use Excel’s MODE function. This function looks at the sorted sequence of data (behind the scenes) then selects the most common value.

Think of the ‘MO’. The MOde function selects the MOst common value.

The structure of the MODE function is

=MODE (number1, number 2 …)

For example:

=MODE(A1:A11)

Wrapping Up

Pulling everything together, here’s how the 3 different functions compare: