Select Date/Time Variable and Duration to Add or Subtract

  1. Select a date (or time) variable.
  2. Select a duration variable or enter a value for Duration Constant. Variables used for durations cannot be date or date/time variables. They can be duration variables or simple numeric variables.
  3. Select the unit that the duration represents from the drop-down list. Select Duration if using a variable and the variable is in the form of a duration, such as hh:mm or hh:mm:ss.