| Value | Category | Cases | |
|---|---|---|---|
| -9 | -9. Don't know | 0 |
0%
|
| -8 | -8. Refused | 0 |
0%
|
| -5 | -5. Not applicable | 0 |
0%
|
| -3 | -3. Missing | 13 |
0.5%
|
| 1 | 1. Months | 593 |
23.7%
|
| 2 | 2. Years | 1900 |
75.8%
|
| Sysmiss | 19368 |