| Value | Category | Cases | |
|---|---|---|---|
| -99 | Do not know | 3 |
4.9%
|
| 2008 | 1 |
1.6%
|
|
| 2010 | 1 |
1.6%
|
|
| 2012 | 1 |
1.6%
|
|
| 2014 | 1 |
1.6%
|
|
| 2015 | 6 |
9.8%
|
|
| 2016 | 19 |
31.1%
|
|
| 2017 | 20 |
32.8%
|
|
| 2018 | 9 |
14.8%
|
|
| Sysmiss | 67 |