There are two main ways to refresh PivotTable data when the source data changes in Excel:

1. Manual Refresh:

* This is the simplest method and is suitable for occasional updates.
* Click anywhere within the PivotTable to activate the Analyze tab.
* In the Data group, click the Refresh button. (Alternatively, press Alt+F5 on your keyboard).

2. Automatic Refresh:

* This method is ideal for situations where the source data is updated frequently.

Option A: Refresh data when opening the file:

* Click anywhere within the PivotTable.
* Go to the Analyze tab and select Options.
* In the Data tab of the PivotTable Options window, check the box for Refresh data when opening the file.
* Click OK.

Option B: VBA code for automatic refresh (more advanced):

* You can write a macro using VBA (Visual Basic for Applications) to automate the refresh process whenever the workbook is opened or the source data is modified. This requires some knowledge of VBA coding.

Here are some additional points to consider:

* PivotCache: When you create a PivotTable, Excel creates a hidden copy of the source data called a PivotCache. This cache is what the PivotTable uses to generate its summaries and analyses. Refreshing the PivotTable updates the PivotCache with the latest data from the source.
* External Data Sources: If your PivotTable is connected to an external data source (like a database), the refresh process might involve specific steps depending on the data source type.

For most users, the manual refresh or the "refresh data when opening the file" option will be sufficient. If you need a more dynamic solution or have complex data connections, consider exploring VBA coding for automatic refresh.