| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 21 |
6.5%
|
| 2008 | 1 |
0.3%
|
|
| 2009 | 1 |
0.3%
|
|
| 2010 | 1 |
0.3%
|
|
| 2012 | 5 |
1.6%
|
|
| 2013 | 5 |
1.6%
|
|
| 2014 | 5 |
1.6%
|
|
| 2015 | 33 |
10.3%
|
|
| 2016 | 39 |
12.1%
|
|
| 2017 | 51 |
15.9%
|
|
| 2018 | 110 |
34.3%
|
|
| 2019 | 49 |
15.3%
|
|
| Sysmiss | 1016 |