| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 5 |
2.4%
|
| 1980 | 1 |
0.5%
|
|
| 1987 | 1 |
0.5%
|
|
| 1990 | 1 |
0.5%
|
|
| 1996 | 1 |
0.5%
|
|
| 2000 | 2 |
0.9%
|
|
| 2002 | 1 |
0.5%
|
|
| 2005 | 1 |
0.5%
|
|
| 2006 | 1 |
0.5%
|
|
| 2007 | 1 |
0.5%
|
|
| 2010 | 4 |
1.9%
|
|
| 2011 | 1 |
0.5%
|
|
| 2012 | 1 |
0.5%
|
|
| 2013 | 2 |
0.9%
|
|
| 2014 | 3 |
1.4%
|
|
| 2015 | 6 |
2.8%
|
|
| 2016 | 2 |
0.9%
|
|
| 2017 | 2 |
0.9%
|
|
| 2018 | 11 |
5.2%
|
|
| 2019 | 18 |
8.5%
|
|
| 2020 | 14 |
6.6%
|
|
| 2021 | 34 |
16%
|
|
| 2022 | 67 |
31.6%
|
|
| 2023 | 32 |
15.1%
|
|
| Sysmiss | 141 |