| Value | Category | Cases | |
|---|---|---|---|
| 2015 | 7 |
0.4%
|
|
| 2016 | 248 |
15.9%
|
|
| 2017 | 271 |
17.3%
|
|
| 2018 | 223 |
14.3%
|
|
| 2019 | 8 |
0.5%
|
|
| 9999 | NO RESPONSE | 2 |
0.1%
|
| Sysmiss | 805 |
51.5%
|