Add a trendline to a data series

1. In the design window, make sure the chart is activated. For instructions, see Help for your design program.
2. Click the data series to which you want to add a trendline.
3. On the chart toolbar, click Commands and Options , and then click the General tab.
4. Under Add, click Add trendline .

Note  A linear trendline, its equation, and its R-squared value are placed on the series. Other trendline types include logarithmic, polynomial, power, exponential, and moving average.