start-time
    Absolute time expression of the start time in the following
    format:
    dd-mmm-yyyy hh:mm:ss.cc
 end-time
    Absolute time expression of the end time in the following format:
    dd-mmm-yyyy hh:mm:ss.cc
 format
    Format for delta time return value. The keywords are as follows:
    o  ASCTIM: ASCII time format
    o  DCL: DCL delta time format This format can be used as an input
       to other DCL time-related lexicals and commands.