| Value | Category | Cases | |
|---|---|---|---|
| 1931 | 1931 | 15 |
1.5%
|
| 1932 | 1932 | 18 |
1.8%
|
| 1933 | 1933 | 15 |
1.5%
|
| 1934 | 1934 | 14 |
1.4%
|
| 1935 | 1935 | 9 |
0.9%
|
| 1936 | 1936 | 12 |
1.2%
|
| 1937 | 1937 | 12 |
1.2%
|
| 1938 | 1938 | 19 |
1.9%
|
| 1939 | 1939 | 15 |
1.5%
|
| 1940 | 1940 | 16 |
1.6%
|
| 1941 | 1941 | 20 |
2%
|
| 1942 | 1942 | 12 |
1.2%
|
| 1943 | 1943 | 25 |
2.5%
|
| 1944 | 1944 | 13 |
1.3%
|
| 1945 | 1945 | 21 |
2.1%
|
| 1946 | 1946 | 29 |
2.9%
|
| 1947 | 1947 | 16 |
1.6%
|
| 1948 | 1948 | 21 |
2.1%
|
| 1949 | 1949 | 12 |
1.2%
|
| 1950 | 1950 | 23 |
2.3%
|
| 1951 | 1951 | 19 |
1.9%
|
| 1952 | 1952 | 14 |
1.4%
|
| 1953 | 1953 | 20 |
2%
|
| 1954 | 1954 | 14 |
1.4%
|
| 1955 | 1955 | 26 |
2.6%
|
| 1956 | 1956 | 17 |
1.7%
|
| 1957 | 1957 | 17 |
1.7%
|
| 1958 | 1958 | 10 |
1%
|
| 1959 | 1959 | 22 |
2.2%
|
| 1960 | 1960 | 11 |
1.1%
|
| 1961 | 1961 | 24 |
2.4%
|
| 1962 | 1962 | 17 |
1.7%
|
| 1963 | 1963 | 18 |
1.8%
|
| 1964 | 1964 | 22 |
2.2%
|
| 1965 | 1965 | 15 |
1.5%
|
| 1966 | 1966 | 35 |
3.5%
|
| 1967 | 1967 | 19 |
1.9%
|
| 1968 | 1968 | 27 |
2.7%
|
| 1969 | 1969 | 25 |
2.5%
|
| 1970 | 1970 | 22 |
2.2%
|
| 1971 | 1971 | 20 |
2%
|
| 1972 | 1972 | 19 |
1.9%
|
| 1973 | 1973 | 15 |
1.5%
|
| 1974 | 1974 | 17 |
1.7%
|
| 1975 | 1975 | 17 |
1.7%
|
| 1976 | 1976 | 24 |
2.4%
|
| 1977 | 1977 | 16 |
1.6%
|
| 1978 | 1978 | 14 |
1.4%
|
| 1979 | 1979 | 11 |
1.1%
|
| 1980 | 1980 | 22 |
2.2%
|
| 1981 | 1981 | 12 |
1.2%
|
| 1982 | 1982 | 25 |
2.5%
|
| 1983 | 1983 | 17 |
1.7%
|
| 1984 | 1984 | 16 |
1.6%
|
| 1985 | 1985 | 12 |
1.2%
|
| 1986 | 1986 | 9 |
0.9%
|
| 1987 | 1987 | 15 |
1.5%
|
| -5 | Missing; Not asked by the interviewer | 0 | |
| -4 | Not asked | 0 | |
| -3 | Not applicable | 0 | |
| -2 | No answer | 0 | |
| -1 | Don´t know | 0 |