Value | Category | Cases | |
---|---|---|---|
-9 | Don't know (spontaneous) | 4 |
0.4%
|
1960 | 2 |
0.2%
|
|
1961 | 1 |
0.1%
|
|
1962 | 1 |
0.1%
|
|
1963 | 2 |
0.2%
|
|
1964 | 1 |
0.1%
|
|
1965 | 1 |
0.1%
|
|
1968 | 1 |
0.1%
|
|
1970 | 3 |
0.3%
|
|
1971 | 1 |
0.1%
|
|
1974 | 1 |
0.1%
|
|
1977 | 1 |
0.1%
|
|
1979 | 4 |
0.4%
|
|
1980 | 5 |
0.5%
|
|
1981 | 2 |
0.2%
|
|
1982 | 6 |
0.6%
|
|
1983 | 1 |
0.1%
|
|
1984 | 2 |
0.2%
|
|
1985 | 3 |
0.3%
|
|
1986 | 2 |
0.2%
|
|
1987 | 3 |
0.3%
|
|
1988 | 5 |
0.5%
|
|
1989 | 1 |
0.1%
|
|
1990 | 16 |
1.6%
|
|
1991 | 4 |
0.4%
|
|
1992 | 5 |
0.5%
|
|
1993 | 9 |
0.9%
|
|
1994 | 5 |
0.5%
|
|
1995 | 10 |
1%
|
|
1996 | 9 |
0.9%
|
|
1997 | 7 |
0.7%
|
|
1998 | 10 |
1%
|
|
1999 | 7 |
0.7%
|
|
2000 | 15 |
1.5%
|
|
2001 | 9 |
0.9%
|
|
2002 | 11 |
1.1%
|
|
2003 | 17 |
1.7%
|
|
2004 | 33 |
3.2%
|
|
2005 | 57 |
5.6%
|
|
2006 | 59 |
5.8%
|
|
2007 | 43 |
4.2%
|
|
2008 | 48 |
4.7%
|
|
2009 | 47 |
4.6%
|
|
2010 | 102 |
10%
|
|
2011 | 55 |
5.4%
|
|
2012 | 46 |
4.5%
|
|
2013 | 53 |
5.2%
|
|
2014 | 32 |
3.1%
|
|
2015 | 50 |
4.9%
|
|
2016 | 31 |
3%
|
|
2017 | 40 |
3.9%
|
|
2018 | 61 |
6%
|
|
2019 | 40 |
3.9%
|
|
2020 | 23 |
2.3%
|
|
2021 | 12 |
1.2%
|