| Value | Category | Cases | |
|---|---|---|---|
| 1970 | 1 |
0.3%
|
|
| 1980 | 3 |
1%
|
|
| 1983 | 2 |
0.7%
|
|
| 1987 | 2 |
0.7%
|
|
| 1990 | 5 |
1.6%
|
|
| 1992 | 1 |
0.3%
|
|
| 1993 | 5 |
1.6%
|
|
| 1995 | 2 |
0.7%
|
|
| 1997 | 2 |
0.7%
|
|
| 1998 | 5 |
1.6%
|
|
| 1999 | 2 |
0.7%
|
|
| 2000 | 24 |
7.9%
|
|
| 2001 | 8 |
2.6%
|
|
| 2002 | 8 |
2.6%
|
|
| 2004 | 7 |
2.3%
|
|
| 2005 | 22 |
7.2%
|
|
| 2006 | 18 |
5.9%
|
|
| 2007 | 31 |
10.2%
|
|
| 2008 | 36 |
11.8%
|
|
| 2009 | 27 |
8.9%
|
|
| 2010 | 63 |
20.7%
|
|
| 2011 | 13 |
4.3%
|
|
| 2012 | 11 |
3.6%
|
|
| 2013 | 6 |
2%
|
|
| Sysmiss | 163 |