| Value | Category |
|---|---|
| 0 | no flag |
| 1 | n > interval since birth |
| 2 | n + amen. > interval |
| 3 | n, but period not returned |
| 4 | 95, but no birth |
| 5 | 95, but period returned |
| 6 | 96, but period returned |
| 7 | n, last period during pregnancy |
| 8 | 96, had children |
| 9 | n, period before last birth |
| Sysmiss |