| Value | Category | Cases | |
|---|---|---|---|
| 1961 | 1 |
0.8%
|
|
| 1962 | 1 |
0.8%
|
|
| 1963 | 4 |
3.1%
|
|
| 1964 | 6 |
4.6%
|
|
| 1965 | 2 |
1.5%
|
|
| 1966 | 4 |
3.1%
|
|
| 1967 | 1 |
0.8%
|
|
| 1968 | 2 |
1.5%
|
|
| 1970 | 6 |
4.6%
|
|
| 1971 | 1 |
0.8%
|
|
| 1972 | 9 |
6.9%
|
|
| 1973 | 4 |
3.1%
|
|
| 1974 | 1 |
0.8%
|
|
| 1975 | 2 |
1.5%
|
|
| 1976 | 2 |
1.5%
|
|
| 1977 | 1 |
0.8%
|
|
| 1978 | 3 |
2.3%
|
|
| 1979 | 8 |
6.2%
|
|
| 1980 | 5 |
3.8%
|
|
| 1981 | 1 |
0.8%
|
|
| 1982 | 5 |
3.8%
|
|
| 1983 | 1 |
0.8%
|
|
| 1984 | 2 |
1.5%
|
|
| 1985 | 4 |
3.1%
|
|
| 1986 | 5 |
3.8%
|
|
| 1987 | 7 |
5.4%
|
|
| 1988 | 3 |
2.3%
|
|
| 1989 | 3 |
2.3%
|
|
| 1990 | 7 |
5.4%
|
|
| 1991 | 4 |
3.1%
|
|
| 1992 | 10 |
7.7%
|
|
| 1993 | 1 |
0.8%
|
|
| 1994 | 11 |
8.5%
|
|
| 1995 | 3 |
2.3%
|