DZ/OZ

This is a 1 digit numeric code distinguishing Origin Zone (OZ) only study areas from those which are also Destination Zone (DZ) study areas.

If a CD is in both DZ and OZ areas then it has a DZ/OZ code = 1.

If a CD is in the OZ area only then it has a DZ/OZ code = 2.

Those CD's not in the OZ area, thus not being in DZ area, have a DZ/OZ code = 0 or Blank.