| Value | Category | Cases | |
|---|---|---|---|
| 1 | 1991 | 4 |
1.8%
|
| 2 | 1996 | 2 |
0.9%
|
| 3 | 1999 | 2 |
0.9%
|
| 4 | 2000 | 2 |
0.9%
|
| 5 | 2001 | 1 |
0.5%
|
| 6 | 2002 | 3 |
1.4%
|
| 7 | 2003 | 2 |
0.9%
|
| 8 | 2004 | 4 |
1.8%
|
| 9 | 2005 | 4 |
1.8%
|
| 10 | 2006 | 1 |
0.5%
|
| 11 | 2007 | 3 |
1.4%
|
| 12 | 2008 | 2 |
0.9%
|
| 13 | 2009 | 7 |
3.2%
|
| 14 | 2010 | 5 |
2.3%
|
| 15 | 2011 | 10 |
4.6%
|
| 16 | 2012 | 16 |
7.4%
|
| 17 | 2013 | 35 |
16.1%
|
| 18 | 2014 | 25 |
11.5%
|
| 19 | 2015 | 23 |
10.6%
|
| 20 | 2016 | 10 |
4.6%
|
| 21 | 2017 | 14 |
6.5%
|
| 22 | 2018 | 28 |
12.9%
|
| 23 | 2019 | 14 |
6.5%
|