| Value | Category | Cases | |
|---|---|---|---|
| 1951 | 1 |
0%
|
|
| 1953 | 1 |
0%
|
|
| 1954 | 1 |
0%
|
|
| 1955 | 1 |
0%
|
|
| 1957 | 2 |
0%
|
|
| 1958 | 8 |
0.1%
|
|
| 1959 | 7 |
0.1%
|
|
| 1960 | 27 |
0.4%
|
|
| 1961 | 34 |
0.5%
|
|
| 1962 | 43 |
0.6%
|
|
| 1963 | 55 |
0.8%
|
|
| 1964 | 62 |
0.9%
|
|
| 1965 | 77 |
1.1%
|
|
| 1966 | 122 |
1.7%
|
|
| 1967 | 107 |
1.5%
|
|
| 1968 | 134 |
1.8%
|
|
| 1969 | 167 |
2.3%
|
|
| 1970 | 208 |
2.9%
|
|
| 1971 | 186 |
2.6%
|
|
| 1972 | 201 |
2.8%
|
|
| 1973 | 238 |
3.3%
|
|
| 1974 | 184 |
2.5%
|
|
| 1975 | 224 |
3.1%
|
|
| 1976 | 213 |
2.9%
|
|
| 1977 | 206 |
2.8%
|
|
| 1978 | 304 |
4.2%
|
|
| 1979 | 477 |
6.6%
|
|
| 1980 | 534 |
7.4%
|
|
| 1981 | 498 |
6.9%
|
|
| 1982 | 498 |
6.9%
|
|
| 1983 | 560 |
7.7%
|
|
| 1984 | 453 |
6.2%
|
|
| 1985 | 388 |
5.3%
|
|
| 1986 | 367 |
5.1%
|
|
| 1987 | 262 |
3.6%
|
|
| 1988 | 213 |
2.9%
|
|
| 1989 | 111 |
1.5%
|
|
| 1990 | 70 |
1%
|
|
| 1991 | 15 |
0.2%
|
|
| 1992 | 4 |
0.1%
|
|
| 1993 | 1 |
0%
|