| Value | Category | Cases | |
|---|---|---|---|
| 2016 | 2 |
0.1%
|
|
| 2017 | 89 |
2.5%
|
|
| 2018 | 114 |
3.2%
|
|
| 9997 | 7 |
0.2%
|
|
| 9999 | NO RESPONSE | 18 |
0.5%
|
| Sysmiss | 3330 |
93.5%
|