The Exponential Smoothing tool in Excel calculates the moving average. However, exponential smoothing weights the values included in the moving average calculations so that more recent values have a bigger effect on the average calculation and old values have a lesser effect. This weighting is accomplished through a smoothing constant. To illustrate how the Exponential … How to add a moving average to an excel stock chart Right click on chart. Click on "Select Data" Click "Add" button. Select cell range $K$23:$K$272. Click OK button. Go to tab "Layout" on the ribbon. Select "Series 4". Click "Format Selection" button, see picture above. Select "Secondary Calculating a rolling average (also known as a moving average) is easy in Excel using the AVERAGE formula combined with absolute and relative cell references. A rolling average helps smooth out trends over time, particularly when your data shows cyclicality by week, month, or year. Let's take a look at what rolling averages are, and how you can calculate them in Excel.