/REAL_SIZE

  The  REAL_SIZE  qualifier  lets  you  specify   the   default   size   for
  floating-point data.

  The format of the REAL_SIZE qualifier is as follows:

     /REAL_SIZE={SINGLE}
                {DOUBLE}
                {GFLOAT}
                {SFLOAT}
                {TFLOAT}
                {XFLOAT}

  The default floating-point size applies to  all  floating-point  variables
  whose size is not explicitly declared.  See the HP BASIC for OpenVMS Alpha
  and VAX Systems User Manual for more information  on  floating-point  data
  types.

  The default is /REAL_SIZE = SFLOAT.