Notation	Name	Description	Status
0	Parent site		stable
1	Observation site		stable
2	Balloon manufacture date		stable
3	Balloon launch point		stable
4	Surface observation		stable
5	Surface observation displacement from launch point		stable
6	Flight level observation		stable
7	Flight level termination point		stable
8	IFR ceiling and visibility		stable
9	Mountain obscuration		stable
10	Strong surface wind		stable
11	Freezing level		stable
12	Multiple freezing level		stable
13	Instrument manufacture date		stable
31	Missing value		stable