Year	per person
1800	0.8279
1820	0.8279
1913	1.279
1950	8.863
1951	9.136
1952	9.416
1953	9.698
1954	9.992
1955	10.3
1956	10.6
1957	10.91
1958	11.23
1959	11.55
1960	11.93
1961	13.62
1962	14.54
1963	15.33
1964	15.91
1965	17.11
1966	17.75
1967	18.33
1968	18.61
1969	19.87
1970	21.25
1971	22.98
1972	25
1973	26.87
1974	36.51
1975	42.39
1976	56
1977	47.69
1978	35.27
1979	34.5
1980	34.42
1981	35.18
1982	33.14
1983	34.01
1984	35.51
1985	33.66
1986	32.39
1987	26.02
1988	28.47
1989	29.96
1990	30.58
1991	31.5
1992	29.65
1993	29.97
1994	30.25
1995	30.93
1996	31.27
1997	32.29
1998	32.66
1999	29.12
2000	27.99
2001	28.04
2002	27.46
2003	27.65
2004	27.56
2005	27.94
2006	27.58
2007	28.33
2008	28.67
2009	27.86