| Value | Category | Cases | |
|---|---|---|---|
| 1975 | 1 |
0%
|
|
| 1976 | 1 |
0%
|
|
| 1977 | 4 |
0.2%
|
|
| 1978 | 2 |
0.1%
|
|
| 1979 | 6 |
0.3%
|
|
| 1980 | 12 |
0.5%
|
|
| 1981 | 4 |
0.2%
|
|
| 1982 | 11 |
0.5%
|
|
| 1983 | 15 |
0.6%
|
|
| 1984 | 13 |
0.5%
|
|
| 1985 | 17 |
0.7%
|
|
| 1986 | 18 |
0.8%
|
|
| 1987 | 25 |
1.1%
|
|
| 1988 | 19 |
0.8%
|
|
| 1989 | 21 |
0.9%
|
|
| 1990 | 16 |
0.7%
|
|
| 1991 | 24 |
1%
|
|
| 1992 | 24 |
1%
|
|
| 1993 | 25 |
1.1%
|
|
| 1994 | 16 |
0.7%
|
|
| 1995 | 24 |
1%
|
|
| 1996 | 28 |
1.2%
|
|
| 1997 | 36 |
1.5%
|
|
| 1998 | 36 |
1.5%
|
|
| 1999 | 35 |
1.5%
|
|
| 2000 | 42 |
1.8%
|
|
| 2001 | 35 |
1.5%
|
|
| 2002 | 37 |
1.6%
|
|
| 2003 | 28 |
1.2%
|
|
| 2004 | 52 |
2.2%
|
|
| 2005 | 33 |
1.4%
|
|
| 2006 | 51 |
2.2%
|
|
| 2007 | 52 |
2.2%
|
|
| 2008 | 59 |
2.5%
|
|
| 2009 | 47 |
2%
|
|
| 2010 | 72 |
3%
|
|
| 2011 | 61 |
2.6%
|
|
| 2012 | 33 |
1.4%
|
|
| 9997 | Inconsistent | 2 |
0.1%
|
| 9998 | DK | 1321 |
55.8%
|
| 9999 | Missing | 11 |
0.5%
|
| Sysmiss | 757 |