The Analysis ToolPak is an Excel 2010 add-in program that adds extra financial, statistical, and engineering functions to Excel's pool of built-in functions. The tools included in the Analysis ToolPak enable you to analyze worksheet data by using ANOVA, F-Test, rank and percentile, t-Test, and Fourier analysis.
Although the Analysis ToolPak comes with Excel 2010, it doesn't come pre-installed. Before you can use the statistical functions added by the Analysis ToolPak, you must install and load it as follows:
Click the File tab and then click Options.
The Excel Options dialog box opens.
Click the Add-Ins tab in the left pane.
The Add-Ins tab contains a list of all the add-in programs installed on your computer.
Select Excel Add-Ins from the Manage drop-down list (at the bottom) and click Go.
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Excel opens the Add-Ins dialog box.
Select the Analysis ToolPak check box in the Add-Ins dialog box and then click OK.
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You might find some other interesting add-ins there, too.
If an alert dialog box asking you if you want to install the add-in appears, click Yes.
Because add-ins often contain macros, and macros can open up your computer to malicious attacks, Microsoft has raised the security level surrounding add-ins.