| Value | Category | Cases | |
|---|---|---|---|
| 0 | 7 |
3.5%
|
|
| 1957 | 1 |
0.5%
|
|
| 1958 | 1 |
0.5%
|
|
| 1968 | 1 |
0.5%
|
|
| 1969 | 1 |
0.5%
|
|
| 1970 | 1 |
0.5%
|
|
| 1974 | 1 |
0.5%
|
|
| 1976 | 2 |
1%
|
|
| 1977 | 1 |
0.5%
|
|
| 1978 | 8 |
4%
|
|
| 1979 | 4 |
2%
|
|
| 1980 | 6 |
3%
|
|
| 1981 | 4 |
2%
|
|
| 1982 | 2 |
1%
|
|
| 1983 | 10 |
5%
|
|
| 1984 | 6 |
3%
|
|
| 1985 | 4 |
2%
|
|
| 1986 | 5 |
2.5%
|
|
| 1987 | 8 |
4%
|
|
| 1988 | 3 |
1.5%
|
|
| 1989 | 8 |
4%
|
|
| 1990 | 8 |
4%
|
|
| 1991 | 7 |
3.5%
|
|
| 1992 | 7 |
3.5%
|
|
| 1993 | 8 |
4%
|
|
| 1994 | 7 |
3.5%
|
|
| 1995 | 6 |
3%
|
|
| 1996 | 6 |
3%
|
|
| 1997 | 7 |
3.5%
|
|
| 1998 | 12 |
6%
|
|
| 1999 | 11 |
5.5%
|
|
| 2000 | 15 |
7.5%
|
|
| 2001 | 15 |
7.5%
|
|
| 2002 | 7 |
3.5%
|
|
| 2003 | 1 |
0.5%
|