| Value | Category | Cases | |
|---|---|---|---|
| 1962 | 8 |
1.7%
|
|
| 1963 | 7 |
1.5%
|
|
| 1964 | 7 |
1.5%
|
|
| 1965 | 6 |
1.3%
|
|
| 1966 | 12 |
2.6%
|
|
| 1967 | 10 |
2.2%
|
|
| 1968 | 11 |
2.4%
|
|
| 1969 | 9 |
1.9%
|
|
| 1970 | 9 |
1.9%
|
|
| 1971 | 11 |
2.4%
|
|
| 1972 | 10 |
2.2%
|
|
| 1973 | 10 |
2.2%
|
|
| 1974 | 7 |
1.5%
|
|
| 1975 | 26 |
5.6%
|
|
| 1976 | 12 |
2.6%
|
|
| 1977 | 8 |
1.7%
|
|
| 1978 | 8 |
1.7%
|
|
| 1979 | 12 |
2.6%
|
|
| 1980 | 24 |
5.2%
|
|
| 1981 | 5 |
1.1%
|
|
| 1982 | 12 |
2.6%
|
|
| 1983 | 15 |
3.2%
|
|
| 1984 | 19 |
4.1%
|
|
| 1985 | 14 |
3%
|
|
| 1986 | 22 |
4.7%
|
|
| 1987 | 10 |
2.2%
|
|
| 1988 | 9 |
1.9%
|
|
| 1989 | 12 |
2.6%
|
|
| 1990 | 24 |
5.2%
|
|
| 1991 | 16 |
3.4%
|
|
| 1992 | 15 |
3.2%
|
|
| 1993 | 20 |
4.3%
|
|
| 1994 | 24 |
5.2%
|
|
| 1995 | 20 |
4.3%
|
|
| 1996 | 21 |
4.5%
|
|
| 9997 | Inconsistent | 0 |
0%
|
| 9998 | DK | 0 |
0%
|
| 9999 | Missing | 0 |
0%
|
| Sysmiss | 53 |