DOY()
 Determines the day of the year for a specific date
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 Syntax

     DOY([<dDate>]) --> nDayOfYear

 Argument

     <dDate>  Designates which date to use to calculate the day of the
     year.  The default is the system date.

 Returns

     DOY() returns a calendar day number that specifies which day of the year
     <dDate> represents.

 Description

     If you frequently work with time periods, then this function is quite
     useful.  DOY() lets you assign a calendar day number to a date that
     relates to the beginning of the year.

 Note

     .  When no date is specified, DOY() uses the system date.
        January 1 is always 1, December 31 is 366 in a leap year; otherwise,
        it is 365.  An empty date returns a 0 result.

 Example

     How long is it until Christmas?

     ? "There are", NTOC(DOY(CTOD("12/24/91"))- DOY())  ;
        , " days until Christmas!"