| Value | Category | Cases | |
|---|---|---|---|
| 2017 | 9 |
0.5%
|
|
| 2018 | 191 |
9.7%
|
|
| 2019 | 165 |
8.4%
|
|
| 9999 | NO RESPONSE | 1 |
0.1%
|
| Sysmiss | 1601 |
81.4%
|