| Value | Category | Cases | |
|---|---|---|---|
| 2015 | 81 |
2.1%
|
|
| 2016 | 1151 |
29.5%
|
|
| 2017 | 1432 |
36.7%
|
|
| 2018 | 1237 |
31.7%
|
|
| 9997 | inconsistent | 0 |
0%
|
| 9998 | don't know | 1 |
0%
|
| Sysmiss | 34544 |