Year	per person
1800	1.645
1820	1.645
1870	1.808
1911	2.185
1912	2.243
1913	2.456
1914	2.511
1915	2.559
1916	2.718
1917	2.821
1918	2.646
1919	3.159
1920	3.03
1921	2.933
1922	3.143
1923	3.029
1924	2.893
1925	3.278
1926	3.593
1927	3.415
1928	3.792
1929	4.591
1930	4.464
1931	4.226
1932	3.812
1933	3.929
1934	4.202
1935	3.724
1936	4.034
1937	3.571
1938	3.715
1939	4.392
1940	3.488
1941	3.38
1942	4.565
1947	2.918
1948	3.234
1949	4.177
1950	4.255
1951	3.93
1952	4.016
1953	3.93
1954	4.067
1955	3.985
1956	4.108
1957	3.969
1958	3.856
1959	4.004
1960	4.176
1961	4.345
1962	4.467
1963	4.555
1964	4.715
1965	4.923
1966	5.039
1967	4.995
1968	5.3
1969	5.473
1970	5.674
1971	5.951
1972	6.248
1973	6.986
1974	7.336
1975	7.228
1976	7.942
1977	8.395
1978	8.925
1979	9.433
1980	9.979
1981	10.43
1982	10.79
1983	11.18
1984	11.76
1985	11.34
1986	11.2
1987	11.51
1988	12.23
1989	13.07
1990	14
1991	15
1992	15.96
1993	17.14
1994	18.3
1995	19.65
1996	21.15
1997	22.22
1998	20.16
1999	20.95
2000	22.28
2001	21.92
2002	22.38
2003	23.24
2004	24.39
2005	25.14
2006	26.17
2007	27.32
2008	28.11
2009	27.17