NZ in null date

[Silvio]

How can effectivly use NZ for the following two expressions? If I live some
record without a date in, I am getting error messages.

CalenDays: DateDiff("d",Date(),[tblProjCycle]![EstDate])

BussDays: workingdays2(Date(),[tblProjCycle]![Estdate])

Please note that wokingdays2 refers to a module that will esclude weekends
and holiday from the calculation.

Thank you,
Silvio

 

[Duane Hookom]

What value would you want to return from the expression if EstDate is null?