"year"	"incidence"
1936	0.9
1937	0.8
1938	0.8
1939	1.3
1940	1.4
1941	1.2
1942	1.7
1943	1.8
1944	1.6
1945	1.5
1946	1.5
1947	2
1948	2.5
1949	2.7
1950	2.9
1951	2.5
1952	3.1
1953	2.4
1954	2.2
1955	2.9
1956	2.5
1957	2.6
1958	3.2
1959	3.8
1960	4.2
1961	3.9
1962	3.7
1963	3.3
1964	3.7
1965	3.9
1966	4.1
1967	3.8
1968	4.7
1969	4.4
1970	4.8
1971	4.8
1972	4.8