How to Calculate R Squared for Measurements in Excel

1. Open a new Excel 2010 spreadsheet. Click on cell 'A1' and type in a header for your measurements. This text will appear at the top of the chart where your R-squared value is located.
2. Click on cell 'A2' and enter your first measurement. Then enter the rest of your measurements down column 'A.'
3. Select cell 'A1' and click the 'Insert' tab at the top of the Excel window. Click the 'Line' button, located in the 'Charts' area of the ribbon. Select the 'Line' option, which will be the icon in the upper-left corner, from the menu that appears. A line chart will appear on your spreadsheet.
4. Click anywhere on the chart to select it, and then click the 'Layout' tab at the top of the screen. Click the 'Trendline' button in the Analysis area of the ribbon, and choose 'More Trendline Options' from the pop-up menu.
5. Click the radio button next to 'Linear' in the Format Trendline window. Then place a check mark next to 'Display R-squared value on chart,' near the bottom of the window. Click 'Close' to close the window. Your R-squared value will appear just above the trendline on the chart.