I understand that you can automatically refresh data that has been imported
from an external source into your excel file, but how do you automatically
refresh the chart that was created from this external data feed?

In article ,
says...
I understand that you can automatically refresh data that has been imported
from an external source into your excel file, but how do you automatically
refresh the chart that was created from this external data feed?

When the data in Excel are updated from the external source, the chart
should also be updated. Make sure Excel's Autocalculation setting is
set to 'Automatic'. If it is and the chart still won't update check
support.microsoft.com for problems with some versions of Excel not
automatically updating charts.