There are two main ways to link charts to external data sources in Excel:

1. Using Excel Data Connection:

This method allows you to connect your chart to an external data source like another Excel file, a text file (CSV), or even a database. Here's a general process:

* Prepare your external data: Ensure your data is organized in a clear table format in the external source.
* Data > From Other Sources: Navigate to the "Data" tab and click "From Other Sources" in the "Get External Data" group.
* Choose data source: Select the type of external data you have (e.g., Excel, Text/CSV, etc.).
* Locate and select the file: Browse to your external data file and select it.
* Import options: Choose whether to create a linked table (recommended for charts) or import a copy of the data.
* Link table creation: In the "Import Data" window, navigate to the "Select Range" section. Choose the table range in your external data source. Optionally, select the "First row contains column headings" checkbox if your first row has column labels.
* Finish import: Click "Import" to establish the connection and create a linked table in your current workbook.
* Create your chart: Select the data range you want to chart (including headers if applicable) from the linked table you just created. Go to the "Insert" tab and choose your desired chart type.
* Benefits: Changes to the data source will be reflected in the chart as long as the link remains intact.

2. Using Paste Link:

This method involves copying the data from the external source and pasting it with a link in your Excel sheet. Here's a basic approach:

* Open both workbooks: Have both your Excel workbook (where you want the chart) and the external data source workbook open.
* Copy data: Select the data range you want to chart in the external source workbook. Right-click and choose "Copy."
* Paste Link: Go to your main workbook and choose the cell where you want the upper-left corner of your data to appear. Right-click and select "Paste Special." Under "Paste Link," choose "Values and Source Formatting" to maintain the data and formatting.
* Create your chart: Select the pasted data range (including headers if applicable) and create your chart using the "Insert" tab.
* Benefits: Similar to data connections, changes in the external source will be reflected in the chart as long as the link is maintained.

Additional Considerations:

* Data source permissions: Ensure you have access rights to modify the external data source if needed.
* Broken links: If the link is broken between the chart and the data source, you'll receive an error message. You can choose to update or edit the link location.
* Data refresh: You can manually refresh the chart data by right-clicking on the chart and selecting "Change Data Source" > "Refresh Data."

These methods provide flexibility for linking charts to external data, allowing you to keep your charts updated with the latest information.