0 0 RESERVED
1 1 ADCP (ACOUSTIC DOPPLER CURRENT PROFILER)
2 2 GEK (GEOMAGNETIC ELECTROKINETOGRAPH)
3 3 SHIP'S SET AND DRIFT DETERMINED BY FIXES 3-6 HOURS APART
4 4 SHIP'S SET AND DRIFT DETERMINED BY FIXES MORE THAN 6 HOURS BUT LESS THAN 12 HOURS APART
5 5 DRIFT OF BUOY
6 6 ADCP (ACOUSTIC DOPPLER CURRENT PROFILER)
7 7 MISSING VALUE
