To use the linear regression tool in Excel, the Data Analysis Toolpak must be installed.
To verify if it is installed, click Data from the Excel menu. If you see the Data Analysis command in the Analysis group (far right), the Data Analysis Toolpak is already installed.
If it is not installed, follow the following directions to install it:
- Click the File menu option, and then click Options.
- Click Add-Ins, and then in the Manage box (near the bottom), select Excel Add-ins.
- Click Go.
- In the Add-Ins available section, select the Analysis ToolPak check box, and then click OK.
The Add-Ins dialog will open. Here, you can select the check box next to Analysis Toolpak (and any other add-ins you want to install). Click OK.
The Data Analysis button (as shown in the first screenshot) should now be available on the Excel Ribbon, under the Data tab. This button will open the Data Analysis dialog, which offers access to a variety of analysis tools.