| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -8 | Refusal (spontaneous) | 0 |
0%
|
| 1 | One year or less | 0 |
0%
|
| 2 | 1 |
16.7%
|
|
| 8 | 1 |
16.7%
|
|
| 12 | 1 |
16.7%
|
|
| 17 | 1 |
16.7%
|
|
| 19 | 1 |
16.7%
|
|
| 20 | 1 |
16.7%
|
|
| Sysmiss | 354 |