15.64.17  DATE 

SET DATE [YYYY\MM\DD] [MONTH=n] [YEAR=n] [DAY=n] [JANUARY,...,DECEMBER]
This  sets  the  base  date  for  date\time values.  Date\time is normally
expressed in hours.  However since it  is  only  single  precision  it  is
accurate  to  only  7  digits or about 1 day on the date 1900.  If greater
accuracy is needed you may set the base date to a value within  the  range
of  time  you need to express.  If you do not specify any options the base 
date is reset to the original default.
(Default:0\1\1)

Options  YEAR,MONTH,  or  DAY  allow you to reset just the selected value.
Instead of MONTH=3 you may also specify MARCH.   All  3  may  be  modified
using the standard YEAR\MONTH\DAY notation.