In this post, I am going to walk you through how to build a stacked bar chart that displays the total value of all series
What you will need to do is add an additional series that will be the total of all series in the chart
In this series, you will add the references to all of the series you would like to sum:
In my case, I wanted to sum the data from 2014 and 2015 to find out how many total sales from both years I had in each quarter
Now you will need to change the properties of this series to be a line chart, select the chart style to be just dots, and check "Show values on chart":