Adding a variance column in an Excel PivotTable is straightforward using the Calculated Field feature, allowing you to compare two different measures or values directly within your aggregated data.
Step-by-Step Guide to Creating a Variance Column
Follow these steps to successfully add a custom variance column to your PivotTable:
- Select a Value Cell in Your PivotTable: Begin by clicking on any cell within the data area (a value field) of your PivotTable. This action typically activates the "PivotTable Analyze" tab on the Excel ribbon.
- Access the "PivotTable Analyze" Tab: Navigate to the "PivotTable Analyze" tab (or simply "Analyze" in some older Excel versions) located in the Excel ribbon at the top of your screen.
- Open "Calculated Field": In the "Calculated Field" group, click on the "Fields, Items, & Sets" dropdown menu, then select "Calculated Field...". This will open the "Insert Calculated Field" dialog box.
- Name Your Variance Field: In the "Name" box, type a descriptive name for your new column, such as "Variance," "Sales Variance," or "Actual vs. Budget Difference."
- Enter Your Variance Formula: In the "Formula" box, construct the calculation for your variance. The most common variance calculation involves subtracting one field from another.
- To add a field to your formula: Select the desired field from the "Fields" list below the formula box and click "Insert Field."
- Example for Actual vs. Budget Variance: If you have data fields named "Actual Sales" and "Budget Sales," your formula might look like this:
='Actual Sales' - 'Budget Sales' - Example for Year-over-Year Variance: If you need to calculate the difference between the current year and the previous year, you'll typically use a separate calculated field for each year or leverage the "Show Values As" feature for difference, then use a calculated field if more complex. For a simple field subtraction:
='Current Year Sales' - 'Previous Year Sales'
- Add and Close: After entering your formula, click the "Add" button, then click "OK." Your new variance field will immediately appear as a new column in your PivotTable and will also be available in the PivotTable Fields pane, ready to be used like any other field.
Understanding Variance Formulas in PivotTables
Variance calculations in PivotTables are incredibly flexible. They allow you to compare various metrics to gain insights into performance, deviations, or trends.
Common types of variance you might calculate include:
- Actual vs. Budget Variance: Measures the difference between what actually happened and what was planned.
- Current Period vs. Previous Period Variance: Shows changes over time, like month-over-month or year-over-year.
- Target vs. Achieved Variance: Compares a set target to the actual outcome.
- Percentage Variance: Calculates the variance as a percentage of a base value, e.g.,
(Actual - Budget) / Budget. This often requires creating two calculated fields (one for the difference, one for the percentage).
Formatting and Displaying Your Variance Column
Once your variance column is added, it's essential to format it for clarity and impact:
- Number Formatting: Right-click on any value in your new variance column, select "Number Format...", and choose an appropriate format such as "Currency," "Number" (with or without decimal places), or "Percentage."
- Conditional Formatting: Apply conditional formatting to visually highlight positive or negative variances. For example, show positive variances in green and negative variances in red to quickly identify areas performing above or below expectations.
- Select the variance column values.
- Go to Home tab > Conditional Formatting > Highlight Cells Rules.
- Choose "Greater Than..." for positive values and "Less Than..." for negative values.
Best Practices for Using Calculated Fields
- Meaningful Names: Always use clear and concise names for your calculated fields to ensure they are easily understood by anyone viewing the PivotTable.
- Test Formulas: Always test your formulas with sample data to ensure they are returning the expected results.
- Understand Limitations: Calculated fields operate on the aggregated data shown in the PivotTable, not on the original source data row by row. Also, a calculated field cannot directly refer to another calculated field in its formula. If you need to base a calculation on another calculated field, you might need to structure your data differently or use multiple simple calculated fields.
- Refresh PivotTable: Remember to refresh your PivotTable (
PivotTable Analyze > Refresh) if your source data changes, to ensure your variance column updates correctly. - Document Formulas: For complex PivotTables, it can be helpful to keep a record of the formulas used in your calculated fields.
By following these steps, you can effectively add and utilize variance columns in your PivotTables, providing valuable insights into your data.
