So, I have used the DateDiff function in the following way to calculate the amount of time in hours between the two exam milestones:

DictationHours: DateDiff("n",[COMPLETED_DT],[DICTATED_DT])/60

How do I not to include Sunday hours in the calculations, since we have no doctors working on sunday to dictate reports. So, I need to calculate the difference between the two dates while excluding Sunday hours.  Can anyone help me to make the necessary adjustments.