| Value | Category | Cases | |
|---|---|---|---|
| 1942 | 1 |
0.4%
|
|
| 1952 | 1 |
0.4%
|
|
| 1956 | 1 |
0.4%
|
|
| 1958 | 2 |
0.9%
|
|
| 1959 | 1 |
0.4%
|
|
| 1960 | 2 |
0.9%
|
|
| 1962 | 2 |
0.9%
|
|
| 1963 | 3 |
1.3%
|
|
| 1964 | 2 |
0.9%
|
|
| 1965 | 3 |
1.3%
|
|
| 1966 | 1 |
0.4%
|
|
| 1967 | 5 |
2.2%
|
|
| 1968 | 2 |
0.9%
|
|
| 1969 | 6 |
2.6%
|
|
| 1970 | 6 |
2.6%
|
|
| 1971 | 6 |
2.6%
|
|
| 1972 | 11 |
4.8%
|
|
| 1973 | 12 |
5.3%
|
|
| 1974 | 13 |
5.7%
|
|
| 1975 | 10 |
4.4%
|
|
| 1976 | 12 |
5.3%
|
|
| 1977 | 17 |
7.5%
|
|
| 1978 | 12 |
5.3%
|
|
| 1979 | 6 |
2.6%
|
|
| 1980 | 11 |
4.8%
|
|
| 1981 | 4 |
1.8%
|
|
| 1982 | 7 |
3.1%
|
|
| 1983 | 6 |
2.6%
|
|
| 1984 | 8 |
3.5%
|
|
| 1985 | 10 |
4.4%
|
|
| 1986 | 9 |
4%
|
|
| 1987 | 6 |
2.6%
|
|
| 1988 | 5 |
2.2%
|
|
| 1989 | 7 |
3.1%
|
|
| 1990 | 3 |
1.3%
|
|
| 1991 | 3 |
1.3%
|
|
| 1992 | 4 |
1.8%
|
|
| 1993 | 2 |
0.9%
|
|
| 9998 | 9998. Don't know | 5 |
2.2%
|
| 9999 | 9999. Missing | 0 |
0%
|
| Sysmiss | 18 |