| Value | Category | Cases | |
|---|---|---|---|
| 0 | NOT GIVEN | 60 |
1.7%
|
| 2015 | 4 |
0.1%
|
|
| 2016 | 14 |
0.4%
|
|
| 2017 | 27 |
0.8%
|
|
| 2018 | 8 |
0.2%
|
|
| Sysmiss | 3361 |
96.7%
|