| Value | Category | Cases | |
|---|---|---|---|
| 1970 | 2 |
0.5%
|
|
| 1973 | 1 |
0.2%
|
|
| 1990 | 1 |
0.2%
|
|
| 2002 | 1 |
0.2%
|
|
| 2003 | 1 |
0.2%
|
|
| 2004 | 4 |
0.9%
|
|
| 2006 | 2 |
0.5%
|
|
| 2010 | 1 |
0.2%
|
|
| 2011 | 13 |
3.1%
|
|
| 2012 | 86 |
20.2%
|
|
| 2013 | 113 |
26.6%
|
|
| 2014 | 23 |
5.4%
|
|
| 2016 | 2 |
0.5%
|
|
| 2017 | 1 |
0.2%
|
|
| 2018 | 3 |
0.7%
|
|
| Missing value | 171 |
40.2%
|