Excel Pivot Tables have a lot of useful calculations under the SHOW VALUES AS option and one that can help you a lot is the PERCENT OF calculation.
It will display the value of one item (the Base Field) as the percentage of another item (the Base Item).
This option will immediately calculate the percentages for you from a table filled with numbers such as sales data, expenses, attendance, or anything that can be quantified.
In the example below I show you how to get the Percent of the Previous Year’s Sales:
STEP 1: Insert a new Pivot table by clicking on your data and going to Insert > Pivot Table > New Worksheet or Existing Worksheet
STEP 2: In the ROWS section put in the Sales Person field, in the COLUMNS put in the Financial Year field and in the VALUES area you need to put in the Sales field twice, I explain why below:
STEP 3: Click the second Sales field’s (Sum of SALES2) drop down and choose Value Field Settings
STEP 4: Select the Show Values As tab and from the drop down choose % of.
For the Base Field pick Financial Year.
For the Base Item pick (previous).
This means we want to get the % of values based on the previous Financial Year.
Also change the Custom Name into Percent of Previous Year to make it more presentable. Click OK.
STEP 5: Notice that the Percent of Previous Year data is in a decimal format that is hard to read:
To format the Percent of Previous Year column, click the second Sales field’s (Percent of Previous Year) drop down and choose Value Field Settings.
The goal here is for us to transform numbers from a decimal format (i.e. 0.23), into a percentage format that is more readable (i.e. 23%).
STEP 6: Click the Number Format button.
STEP 7: Inside the Format Cells dialog box, make your formatting changes within here and press OK twice.
In this example, we used the Percentage category to make our Percent of Previous Year numbers become more readable.
You now have your Pivot Table, showing the Percent of Previous Year for the sales data of years 2012, 2013, and 2014.
All of the sales numbers are now represented as a Percentage of the Previous Year (Year 2013 is represented as a Percentage of Year 2012, and Year 2014 is represented as a Percentage of Year 2013):