| Value | Category | Cases | |
|---|---|---|---|
| 2015 | 4 |
0.1%
|
|
| 2016 | 386 |
14.4%
|
|
| 2017 | 1249 |
46.5%
|
|
| 2018 | 1045 |
38.9%
|
|
| 9997 | inconsistent | 0 |
0%
|
| 9998 | don't know | 2 |
0.1%
|
| Sysmiss | 35760 |