Each variable record represents a single variable. Variable records have tag code 7. They have the following structure:
Each variable record can optionally be followed by a missing value record, which has tag code 8. A missing value record has one field, the missing value itself (a floating-point or string, as appropriate). Up to three of these missing value records can be used.
There is also a record for missing value ranges, which has tag code B. It is followed by two fields representing the range, which are floating-point or string as appropriate. If a missing value range is present, it may be followed by a single missing value record.
Tag codes 9 and A represent LO THRU
x and
x THRU HI
ranges, respectively. Each is followed by a
single field representing x. If one of the ranges is present, it
may be followed by a single missing value record.
In addition, each variable record can optionally be followed by a variable label record, which has tag code C. A variable label record has one field, the variable label itself (string).