Year	per person
1800	0.7993
1820	0.7993
1913	1.235
1950	2.326
1951	2.42
1952	2.516
1953	2.616
1954	2.717
1955	2.59
1956	2.827
1957	2.877
1958	2.732
1959	3.22
1960	3.379
1961	3.302
1962	3.186
1963	3.175
1964	3.507
1965	4.039
1966	3.718
1967	3.897
1968	3.844
1969	3.718
1970	3.777
1971	3.668
1972	3.889
1973	3.738
1974	3.923
1975	3.663
1976	3.77
1977	3.484
1978	3.405
1979	3.205
1980	3.205
1981	3.295
1982	3.089
1983	2.916
1984	2.805
1985	2.761
1986	2.684
1987	2.661
1988	2.741
1989	2.69
1990	2.851
1991	2.774
1992	2.655
1993	2.766
1994	2.342
1995	2.232
1996	2.326
1997	2.349
1998	2.253
1999	2.249
2000	2.272
2001	2.324
2002	2.35
2003	2.424
2004	2.502
2005	2.577
2006	2.673
2007	2.925
2008	3.032
2009	3.162