Double-click on the **Chart** you would like to edit\
Navigate to the **Chart Series tab**\
Click the **Plus icon**\
In the **Measure Series dropdown**, select the series you would like the previous year series to be based on\
Under **Label**, enter the name of the new Series, for example, ‘Last Year’.\
Use **Series Options** to adjust the **Shape**, assign a **Marker type**, change the **Color**