| Value | Category | Cases | |
|---|---|---|---|
| 1968 | 2 |
1.7%
|
|
| 1973 | 1 |
0.8%
|
|
| 1976 | 1 |
0.8%
|
|
| 1978 | 1 |
0.8%
|
|
| 1980 | 4 |
3.3%
|
|
| 1984 | 1 |
0.8%
|
|
| 1985 | 1 |
0.8%
|
|
| 1986 | 1 |
0.8%
|
|
| 1988 | 1 |
0.8%
|
|
| 1989 | 1 |
0.8%
|
|
| 1990 | 2 |
1.7%
|
|
| 1992 | 1 |
0.8%
|
|
| 1995 | 1 |
0.8%
|
|
| 1997 | 2 |
1.7%
|
|
| 1998 | 1 |
0.8%
|
|
| 1999 | 3 |
2.5%
|
|
| 2000 | 2 |
1.7%
|
|
| 2002 | 1 |
0.8%
|
|
| 2003 | 1 |
0.8%
|
|
| 2004 | 1 |
0.8%
|
|
| 2005 | 1 |
0.8%
|
|
| 2006 | 1 |
0.8%
|
|
| 2007 | 3 |
2.5%
|
|
| 2008 | 1 |
0.8%
|
|
| 2009 | 2 |
1.7%
|
|
| 2010 | 2 |
1.7%
|
|
| 2011 | 1 |
0.8%
|
|
| 2012 | 3 |
2.5%
|
|
| 2013 | 3 |
2.5%
|
|
| 2014 | 4 |
3.3%
|
|
| 2015 | 11 |
9.1%
|
|
| 2016 | 33 |
27.3%
|
|
| 2017 | 27 |
22.3%
|
|
| Sysmiss | 5237 |