| Value | Category | Cases | |
|---|---|---|---|
| 1972 | 2 |
0.1%
|
|
| 1973 | 4 |
0.2%
|
|
| 1974 | 6 |
0.3%
|
|
| 1975 | 9 |
0.5%
|
|
| 1976 | 14 |
0.7%
|
|
| 1977 | 18 |
0.9%
|
|
| 1978 | 12 |
0.6%
|
|
| 1979 | 19 |
1%
|
|
| 1980 | 27 |
1.4%
|
|
| 1981 | 26 |
1.4%
|
|
| 1982 | 29 |
1.5%
|
|
| 1983 | 28 |
1.5%
|
|
| 1984 | 32 |
1.7%
|
|
| 1985 | 37 |
1.9%
|
|
| 1986 | 47 |
2.5%
|
|
| 1987 | 34 |
1.8%
|
|
| 1988 | 37 |
1.9%
|
|
| 1989 | 44 |
2.3%
|
|
| 1990 | 55 |
2.9%
|
|
| 1991 | 51 |
2.7%
|
|
| 1992 | 44 |
2.3%
|
|
| 1993 | 42 |
2.2%
|
|
| 1994 | 52 |
2.7%
|
|
| 1995 | 54 |
2.8%
|
|
| 1996 | 68 |
3.6%
|
|
| 1997 | 55 |
2.9%
|
|
| 1998 | 68 |
3.6%
|
|
| 1999 | 59 |
3.1%
|
|
| 2000 | 96 |
5%
|
|
| 2001 | 60 |
3.1%
|
|
| 2002 | 52 |
2.7%
|
|
| 2003 | 68 |
3.6%
|
|
| 2004 | 55 |
2.9%
|
|
| 2005 | 74 |
3.9%
|
|
| 2006 | 74 |
3.9%
|
|
| 2007 | 60 |
3.1%
|
|
| 2008 | 80 |
4.2%
|
|
| 2009 | 66 |
3.4%
|
|
| 2010 | 62 |
3.2%
|
|
| 2011 | 27 |
1.4%
|
|
| 9997 | Inconsistent | 0 |
0%
|
| 9998 | DK | 167 |
8.7%
|
| 9999 | Missing | 0 |
0%
|
| Sysmiss | 1597 |