Year	per person
1800	1.076
1820	1.099
1870	0.8829
1890	1.243
1900	1.33
1910	1.558
1913	1.558
1920	1.52
1921	1.535
1922	1.558
1923	1.616
1924	1.707
1925	1.766
1926	1.862
1927	1.806
1928	1.937
1929	2.011
1930	1.943
1931	1.858
1932	1.662
1933	1.69
1934	1.729
1935	1.68
1936	1.872
1937	1.877
1938	1.999
1939	2.081
1947	1.939
1948	2.282
1949	2.474
1950	2.286
1951	2.345
1952	2.135
1953	2.421
1954	2.523
1955	2.649
1956	2.567
1957	2.969
1958	3.066
1959	3.41
1960	3.592
1961	3.717
1962	3.749
1963	4.1
1964	4.45
1965	4.526
1966	4.724
1967	4.764
1968	4.824
1969	5.321
1970	5.534
1971	6.118
1972	6.272
1973	6.428
1974	7.192
1975	7.129
1976	7.28
1977	7.738
1978	8.094
1979	8.577
1980	8.937
1981	9.042
1982	9.05
1983	9.076
1984	9.255
1985	9.281
1986	9.613
1987	9.461
1988	9.287
1989	9.129
1990	8.431
1991	7.409
1992	5.585
1993	4.157
1994	4.461
1995	4.826
1996	7.649
1997	10.45
1998	11.52
1999	12.16
2000	12.57
2001	12.9
2002	13.2
2003	13.37
2004	13.85
2005	14.27
2006	15.04
2007	15.89
2008	16.71
2009	16.1