I apologize, I should have been more specific.  We do use the Exclude Weekends for Saturday and Sunday, however our district, like many others, has 3 day weekends in the summer.  So for 2 months out of the year, we are on a 4 day work week.  This is what I was referring to.  It's not technically a Holiday, but we do have several other days during the year that are not official holidays but our offices are closed.  Has there been any move on including Holidays or a customized calendar?

In the "Date Filter" dropdown, there is a checkbox "Exclude Saturdays and Sundays when calculating durations", you can check it to exclude weekends, exclude holidays are not supported yet, but it has been requested before.