DATECALC()     Adds/subtracts days,weeks,months,years to a date
 DTOW()         Converts date to words
 STOD()         Returns date from string in the form YYYYMMDD
 WOYEAR()       Calculates week of the year (# of 7 day periods)
 DTDIFF()       Returns difference between dates
 DAYSIN()       Calculates number of days in a month
 BOYEAR()       Determine beginning of year a date falls in
 BOM()          Calculates beginning of the month date
 DOYEAR()       Calculates day of the year from date
 SETCENT()      Determines if century is on/off
 WOMONTH()      Calculates week of the month (# of 7 day periods)
 BEGEND()       Determines beginning or end of week,month or quarter
 SET_DATE()     Sets and restores date format