When analysing business processes which have a start time and end time, it's not uncommon for KPIs to require the business duration between those times. Until now, if I was measuring business days between dates, I was doing it in DAX using my DimCalendar table, similar to this article at SQLBI.com. It's very fast and is not a big performance hit on your data model. Recently I had a requirement to do business hours calculations, accurate to minute level. I chose Power Query to