| Value | Category | Cases | |
|---|---|---|---|
| 1991 | 2 |
0.1%
|
|
| 1992 | 1 |
0.1%
|
|
| 1994 | 3 |
0.2%
|
|
| 1995 | 3 |
0.2%
|
|
| 1996 | 6 |
0.3%
|
|
| 1997 | 1 |
0.1%
|
|
| 1998 | 2 |
0.1%
|
|
| 2000 | 2 |
0.1%
|
|
| 2001 | 3 |
0.2%
|
|
| 2002 | 1 |
0.1%
|
|
| 2003 | 3 |
0.2%
|
|
| 2004 | 1 |
0.1%
|
|
| 2005 | 5 |
0.3%
|
|
| 2006 | 5 |
0.3%
|
|
| 2007 | 8 |
0.4%
|
|
| 2008 | 20 |
1.1%
|
|
| 2009 | 11 |
0.6%
|
|
| 2010 | 11 |
0.6%
|
|
| 2011 | 4 |
0.2%
|
|
| 2012 | 22 |
1.2%
|
|
| 2014 | 1 |
0.1%
|
|
| 2015 | 2 |
0.1%
|
|
| 2017 | 1548 |
86.6%
|
|
| 2018 | 67 |
3.7%
|
|
| Missing value | 56 |
3.1%
|