| Value | Category | Cases | |
|---|---|---|---|
| 1974 | 2 |
0.2%
|
|
| 1977 | 6 |
0.7%
|
|
| 1978 | 10 |
1.1%
|
|
| 1979 | 10 |
1.1%
|
|
| 1980 | 14 |
1.5%
|
|
| 1981 | 16 |
1.7%
|
|
| 1982 | 14 |
1.5%
|
|
| 1983 | 13 |
1.4%
|
|
| 1984 | 18 |
2%
|
|
| 1985 | 25 |
2.7%
|
|
| 1986 | 13 |
1.4%
|
|
| 1987 | 24 |
2.6%
|
|
| 1988 | 21 |
2.3%
|
|
| 1989 | 19 |
2.1%
|
|
| 1990 | 39 |
4.2%
|
|
| 1991 | 32 |
3.5%
|
|
| 1992 | 31 |
3.4%
|
|
| 1993 | 22 |
2.4%
|
|
| 1994 | 32 |
3.5%
|
|
| 1995 | 39 |
4.2%
|
|
| 1996 | 24 |
2.6%
|
|
| 1997 | 33 |
3.6%
|
|
| 1998 | 23 |
2.5%
|
|
| 1999 | 40 |
4.3%
|
|
| 2000 | 51 |
5.5%
|
|
| 2001 | 42 |
4.6%
|
|
| 2002 | 44 |
4.8%
|
|
| 2003 | 42 |
4.6%
|
|
| 2004 | 48 |
5.2%
|
|
| 2005 | 54 |
5.9%
|
|
| 2006 | 59 |
6.4%
|
|
| 2007 | 56 |
6.1%
|
|
| 9997 | Inconsistent | 5 |
0.5%
|
| 9998 | DK | 0 |
0%
|
| Sysmiss | 9449 |