Microsoft Support Help Article 183446 (How to use defined names to automatically update a chart range in Excel) does not state it applies to Excel 2016. I have though tried using the instructions given in Method 1 for Microsoft Office Excel 2007, 2010 and 2013 in Microsoft Excel 2016 MSO (16.0.9126.2336) 32-bit within a Chart that uses the Stacked Bar Chart Type simulate a Gantt Chart from Start Date, Duration, and Task Description columns. The chart displays correctly when the defined names are first created and the Chart’s Select Data… is first modified, but adding additional cell data does not auto-update the Chart. Clearly the rand()*0 is not volatile enough in 2016. So what can I use?
I agree. Using a Table within the Excel sheet in this instance is by far the easiest technique to use, the reference method is a lot easier too: "=<table_name>[<column_name>]". The chart now automatically updates as soon as the table is extended/shrunk in rows.