| Value | Category | Cases | |
|---|---|---|---|
| 2016 | 2 |
0.1%
|
|
| 2017 | 253 |
8.6%
|
|
| 2018 | 408 |
13.9%
|
|
| 2019 | 319 |
10.9%
|
|
| 9999 | NO RESPONSE | 2 |
0.1%
|
| Sysmiss | 1941 |
66.4%
|