| Value | Category | Cases | |
|---|---|---|---|
| 1965 | 1 |
0.3%
|
|
| 1966 | 1 |
0.3%
|
|
| 1968 | 2 |
0.6%
|
|
| 1969 | 2 |
0.6%
|
|
| 1971 | 1 |
0.3%
|
|
| 1972 | 1 |
0.3%
|
|
| 1974 | 2 |
0.6%
|
|
| 1975 | 2 |
0.6%
|
|
| 1976 | 1 |
0.3%
|
|
| 1977 | 1 |
0.3%
|
|
| 1979 | 4 |
1.2%
|
|
| 1980 | 4 |
1.2%
|
|
| 1981 | 6 |
1.8%
|
|
| 1982 | 9 |
2.7%
|
|
| 1983 | 5 |
1.5%
|
|
| 1984 | 4 |
1.2%
|
|
| 1985 | 6 |
1.8%
|
|
| 1986 | 4 |
1.2%
|
|
| 1987 | 6 |
1.8%
|
|
| 1988 | 5 |
1.5%
|
|
| 1989 | 8 |
2.4%
|
|
| 1990 | 3 |
0.9%
|
|
| 1991 | 2 |
0.6%
|
|
| 1992 | 4 |
1.2%
|
|
| 1993 | 3 |
0.9%
|
|
| 1994 | 4 |
1.2%
|
|
| 1995 | 5 |
1.5%
|
|
| 1996 | 5 |
1.5%
|
|
| 1997 | 4 |
1.2%
|
|
| 1998 | 3 |
0.9%
|
|
| 1999 | 9 |
2.7%
|
|
| 2000 | 9 |
2.7%
|
|
| 2001 | 9 |
2.7%
|
|
| 2002 | 16 |
4.7%
|
|
| 2003 | 18 |
5.3%
|
|
| 2004 | 18 |
5.3%
|
|
| 2005 | 28 |
8.3%
|
|
| 2006 | 22 |
6.5%
|
|
| 2007 | 23 |
6.8%
|
|
| 2008 | 23 |
6.8%
|
|
| 2009 | 23 |
6.8%
|
|
| 2010 | 14 |
4.1%
|
|
| 2011 | 11 |
3.2%
|
|
| 2012 | 6 |
1.8%
|
|
| 2013 | 1 |
0.3%
|
|
| 9998 | 9998. Don't know | 0 |
0%
|
| 9999 | 9999. Missing | 1 |
0.3%
|