| Value | Category | Cases | |
|---|---|---|---|
| 1 | 6 months | 92 |
8%
|
| 2 | 6 to 12 months | 109 |
9.5%
|
| 3 | More than 1 year | 254 |
22.2%
|
| 98 | Don't know | 691 |
60.3%
|
| Sysmiss | 357 |