| Value | Category | Cases | |
|---|---|---|---|
| 1991 | 8 |
2%
|
|
| 1992 | 24 |
6%
|
|
| 1993 | 11 |
2.7%
|
|
| 1994 | 11 |
2.7%
|
|
| 1995 | 8 |
2%
|
|
| 1996 | 11 |
2.7%
|
|
| 1997 | 11 |
2.7%
|
|
| 1998 | 20 |
5%
|
|
| 1999 | 22 |
5.5%
|
|
| 2000 | 9 |
2.2%
|
|
| 2001 | 5 |
1.2%
|
|
| 2002 | 3 |
0.7%
|
|
| 2003 | 5 |
1.2%
|
|
| 2004 | 5 |
1.2%
|
|
| 2005 | 2 |
0.5%
|
|
| 2006 | 6 |
1.5%
|
|
| 2007 | 4 |
1%
|
|
| 2008 | 15 |
3.7%
|
|
| 2009 | 11 |
2.7%
|
|
| 2010 | 5 |
1.2%
|
|
| 2011 | 4 |
1%
|
|
| 2012 | 7 |
1.7%
|
|
| 2013 | 3 |
0.7%
|
|
| 2014 | 7 |
1.7%
|
|
| 2015 | 5 |
1.2%
|
|
| 2016 | 2 |
0.5%
|
|
| 2017 | 4 |
1%
|
|
| 2018 | 2 |
0.5%
|
|
| Missing value | 171 |
42.6%
|