title: Calculated Column DAX Formula for Date Is Less Than Last Friday
body: <p>I need to add a calculated column that returns 'Yes' if the row's date (<code>datekey</code> on this date table) is on or before last Friday, 'No' otherwise. </p>
  
  <p>To start, I've got <code>IF(DimDate[DateKey] &lt; DATEVALUE("2017-10-27"), "Yes", "No")</code> however, I obviously need the <code>2017-10-27</code> date to be dynamic. </p>
  
  <p>Is there an application of the DATEDIFF function that will return the date of the last Friday?</p>