Year	per person
1800	2.044
1820	2.044
1870	3.106
1913	5.729
1950	11.66
1951	10.22
1952	10.6
1953	11.92
1954	13.36
1955	14.09
1956	13.44
1957	13.35
1958	11.19
1959	11.85
1960	11.88
1961	12.36
1962	12.53
1963	12.33
1964	12.75
1965	13.66
1966	14.21
1967	13.17
1968	14.44
1969	14.38
1970	14.97
1971	15.46
1972	16.42
1973	16.36
1974	18.22
1975	18.07
1976	18.45
1977	18.99
1978	19.57
1979	18.56
1980	18.71
1981	17.91
1982	16.76
1983	16.63
1984	17.03
1985	17.52
1986	16.81
1987	11.79
1988	10.74
1989	10.75
1990	10.63
1991	14.53
1992	15.11
1993	16.06
1994	17.2
1995	18.14
1996	18.66
1997	19.2
1998	19.56
1999	19.2
2000	19.32
2001	19.98
2002	20.43
2003	21.05
2004	22.38
2005	22.39
2006	22.49
2007	24.18
2008	26.02
2009	28