Year	per person
1800	1.935
1820	1.945
1913	3.336
1950	8.335
1951	9.346
1952	8.962
1953	8.611
1954	9.984
1955	10.95
1956	11.42
1957	11.81
1958	12.16
1959	13.32
1960	13.8
1961	14.78
1962	15.58
1963	16.55
1964	17.5
1965	18.56
1966	18.31
1967	18.41
1968	20.81
1969	22.85
1970	23.97
1971	25.77
1972	28.04
1973	28.54
1974	29.66
1975	30.02
1976	29.8
1977	29.18
1978	29.96
1979	31.11
1980	32.5
1981	33.6
1982	33.7
1983	34.28
1984	33.91
1985	34.48
1986	35.59
1987	37.55
1988	37.69
1989	37.39
1990	38.37
1991	38.47
1992	39.59
1993	39.92
1994	42.32
1995	44.18
1996	45.27
1997	45.83
1998	46.3
1999	46.78
2000	50.08
2001	49.07
2002	48.04
2003	48.44
2004	50.29
2005	52.29
2006	54.09
2007	55.68
2008	56.67
2009	55.84