| Value | Category | Cases | |
|---|---|---|---|
| 1960 | 1 |
0.4%
|
|
| 1965 | 1 |
0.4%
|
|
| 1966 | 1 |
0.4%
|
|
| 1971 | 3 |
1.2%
|
|
| 1974 | 1 |
0.4%
|
|
| 1975 | 6 |
2.4%
|
|
| 1976 | 6 |
2.4%
|
|
| 1977 | 3 |
1.2%
|
|
| 1978 | 3 |
1.2%
|
|
| 1979 | 7 |
2.7%
|
|
| 1981 | 5 |
2%
|
|
| 1982 | 5 |
2%
|
|
| 1983 | 4 |
1.6%
|
|
| 1984 | 4 |
1.6%
|
|
| 1985 | 5 |
2%
|
|
| 1986 | 8 |
3.1%
|
|
| 1987 | 8 |
3.1%
|
|
| 1988 | 5 |
2%
|
|
| 1989 | 5 |
2%
|
|
| 1990 | 8 |
3.1%
|
|
| 1991 | 10 |
3.9%
|
|
| 1992 | 11 |
4.3%
|
|
| 1993 | 5 |
2%
|
|
| 1994 | 16 |
6.3%
|
|
| 1995 | 5 |
2%
|
|
| 1996 | 1 |
0.4%
|
|
| 1997 | 6 |
2.4%
|
|
| 1998 | 7 |
2.7%
|
|
| 1999 | 7 |
2.7%
|
|
| 2000 | 5 |
2%
|
|
| 2001 | 5 |
2%
|
|
| 2002 | 6 |
2.4%
|
|
| 2003 | 5 |
2%
|
|
| 2004 | 5 |
2%
|
|
| 2005 | 4 |
1.6%
|
|
| 2006 | 3 |
1.2%
|
|
| 2007 | 2 |
0.8%
|
|
| 2008 | 4 |
1.6%
|
|
| 2009 | 4 |
1.6%
|
|
| 2010 | 5 |
2%
|
|
| 2011 | 4 |
1.6%
|
|
| 2012 | 4 |
1.6%
|
|
| 2013 | 3 |
1.2%
|
|
| 9998 | don't know | 39 |
15.3%
|
| Sysmiss | 16175 |