| Value | Category | Cases | |
|---|---|---|---|
| 2015 | 32 |
0.9%
|
|
| 2016 | 384 |
10.8%
|
|
| 2017 | 404 |
11.3%
|
|
| 2018 | 230 |
6.5%
|
|
| 9997 | 8 |
0.2%
|
|
| 9999 | NO RESPONSE | 18 |
0.5%
|
| Sysmiss | 2484 |
69.8%
|