Value | Category | Cases | |
---|---|---|---|
-9 | Don't know (spontaneous) | 4 |
0.6%
|
1946 | 1 |
0.1%
|
|
1953 | 1 |
0.1%
|
|
1960 | 1 |
0.1%
|
|
1965 | 1 |
0.1%
|
|
1966 | 1 |
0.1%
|
|
1970 | 2 |
0.3%
|
|
1973 | 1 |
0.1%
|
|
1974 | 1 |
0.1%
|
|
1976 | 2 |
0.3%
|
|
1978 | 2 |
0.3%
|
|
1979 | 1 |
0.1%
|
|
1980 | 1 |
0.1%
|
|
1982 | 2 |
0.3%
|
|
1983 | 1 |
0.1%
|
|
1984 | 2 |
0.3%
|
|
1985 | 2 |
0.3%
|
|
1986 | 1 |
0.1%
|
|
1987 | 3 |
0.4%
|
|
1988 | 4 |
0.6%
|
|
1989 | 1 |
0.1%
|
|
1990 | 3 |
0.4%
|
|
1991 | 3 |
0.4%
|
|
1992 | 6 |
0.8%
|
|
1993 | 9 |
1.3%
|
|
1994 | 2 |
0.3%
|
|
1995 | 8 |
1.1%
|
|
1996 | 8 |
1.1%
|
|
1997 | 4 |
0.6%
|
|
1998 | 15 |
2.1%
|
|
1999 | 2 |
0.3%
|
|
2000 | 20 |
2.8%
|
|
2001 | 13 |
1.8%
|
|
2002 | 10 |
1.4%
|
|
2003 | 19 |
2.7%
|
|
2004 | 14 |
2%
|
|
2005 | 16 |
2.2%
|
|
2006 | 20 |
2.8%
|
|
2007 | 20 |
2.8%
|
|
2008 | 42 |
5.9%
|
|
2009 | 24 |
3.4%
|
|
2010 | 33 |
4.6%
|
|
2011 | 20 |
2.8%
|
|
2012 | 34 |
4.8%
|
|
2013 | 28 |
3.9%
|
|
2014 | 35 |
4.9%
|
|
2015 | 46 |
6.5%
|
|
2016 | 46 |
6.5%
|
|
2017 | 25 |
3.5%
|
|
2018 | 49 |
6.9%
|
|
2019 | 45 |
6.3%
|
|
2020 | 30 |
4.2%
|
|
2021 | 18 |
2.5%
|
|
2022 | 11 |
1.5%
|