| Value | Category | Cases | |
|---|---|---|---|
| 1 | Month and year | 34768 |
92.3%
|
| 2 | Month and age -y imp | 3 |
0%
|
| 3 | Year and age - m imp | 1910 |
5.1%
|
| 6 | Age - y, m imp | 22 |
0.1%
|
| Sysmiss | 966 |
2.6%
|