| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 8 |
3.7%
|
| 0 | Less than one year | 22 |
10%
|
| 1 | 82 |
37.4%
|
|
| 2 | 28 |
12.8%
|
|
| 3 | 20 |
9.1%
|
|
| 4 | 7 |
3.2%
|
|
| 5 | 15 |
6.8%
|
|
| 6 | 3 |
1.4%
|
|
| 7 | 2 |
0.9%
|
|
| 8 | 7 |
3.2%
|
|
| 9 | 3 |
1.4%
|
|
| 10 | 8 |
3.7%
|
|
| 12 | 2 |
0.9%
|
|
| 13 | 2 |
0.9%
|
|
| 14 | 1 |
0.5%
|
|
| 15 | 6 |
2.7%
|
|
| 17 | 1 |
0.5%
|
|
| 18 | 1 |
0.5%
|
|
| 28 | 1 |
0.5%
|
|
| Sysmiss | 335 |