| Value | Category | Cases | |
|---|---|---|---|
| 1956 | 40 |
0.3%
|
|
| 1957 | 347 |
2.3%
|
|
| 1958 | 502 |
3.4%
|
|
| 1959 | 512 |
3.4%
|
|
| 1960 | 539 |
3.6%
|
|
| 1961 | 575 |
3.9%
|
|
| 1962 | 533 |
3.6%
|
|
| 1963 | 543 |
3.6%
|
|
| 1964 | 512 |
3.4%
|
|
| 1965 | 572 |
3.8%
|
|
| 1966 | 525 |
3.5%
|
|
| 1967 | 538 |
3.6%
|
|
| 1968 | 574 |
3.9%
|
|
| 1969 | 557 |
3.7%
|
|
| 1970 | 495 |
3.3%
|
|
| 1971 | 550 |
3.7%
|
|
| 1972 | 568 |
3.8%
|
|
| 1973 | 514 |
3.4%
|
|
| 1974 | 540 |
3.6%
|
|
| 1975 | 555 |
3.7%
|
|
| 1976 | 488 |
3.3%
|
|
| 1977 | 495 |
3.3%
|
|
| 1978 | 523 |
3.5%
|
|
| 1979 | 525 |
3.5%
|
|
| 1980 | 506 |
3.4%
|
|
| 1981 | 434 |
2.9%
|
|
| 1982 | 415 |
2.8%
|
|
| 1983 | 349 |
2.3%
|
|
| 1984 | 284 |
1.9%
|
|
| 1985 | 257 |
1.7%
|
|
| 1986 | 184 |
1.2%
|
|
| 1987 | 151 |
1%
|
|
| 1988 | 108 |
0.7%
|
|
| 1989 | 62 |
0.4%
|
|
| 1990 | 21 |
0.1%
|
|
| 1991 | 12 |
0.1%
|
|
| 1992 | 3 |
0%
|
|
| 9997 | Inconsistent | 0 |
0%
|
| 9998 | DK year | 0 |
0%
|
| 9999 | 1 |