| Value | Category | Cases | |
|---|---|---|---|
| -98 | Don't know | 30 |
2.1%
|
| 1 | Less than 6 months | 37 |
2.6%
|
| 2 | 6 months | 1007 |
70.3%
|
| 3 | More than 6 months | 359 |
25.1%
|
| Sysmiss | 776 |