| Value | Category | Cases | |
|---|---|---|---|
| 1978 | 10 |
0.1%
|
|
| 1979 | 11 |
0.1%
|
|
| 1980 | 31 |
0.4%
|
|
| 1981 | 14 |
0.2%
|
|
| 1982 | 92 |
1.2%
|
|
| 1983 | 31 |
0.4%
|
|
| 1984 | 75 |
0.9%
|
|
| 1985 | 101 |
1.3%
|
|
| 1986 | 84 |
1.1%
|
|
| 1987 | 70 |
0.9%
|
|
| 1988 | 118 |
1.5%
|
|
| 1989 | 146 |
1.8%
|
|
| 1990 | 192 |
2.4%
|
|
| 1991 | 204 |
2.6%
|
|
| 1992 | 289 |
3.6%
|
|
| 1993 | 273 |
3.4%
|
|
| 1994 | 295 |
3.7%
|
|
| 1995 | 401 |
5.1%
|
|
| 1996 | 357 |
4.5%
|
|
| 1997 | 405 |
5.1%
|
|
| 1998 | 452 |
5.7%
|
|
| 1999 | 473 |
6%
|
|
| 2000 | 624 |
7.9%
|
|
| 2001 | 506 |
6.4%
|
|
| 2002 | 624 |
7.9%
|
|
| 2003 | 931 |
11.8%
|
|
| 2004 | 1108 |
14%
|
|
| 9997 | inconsistent | 0 |
0%
|
| 9998 | don't know | 1 |
0%
|
| 10001 | .Z | 29593 |