Year	per person
1800	1.331
1820	1.331
1950	1.625
1951	1.67
1952	1.725
1953	1.775
1954	1.83
1955	1.884
1956	1.94
1957	2.001
1958	2.06
1959	2.122
1960	2.186
1961	2.251
1962	2.317
1963	2.389
1964	2.46
1965	2.534
1966	2.608
1967	2.689
1968	2.769
1969	2.85
1970	2.938
1971	3.028
1972	3.118
1973	3.211
1974	3.308
1975	3.406
1976	3.504
1977	3.613
1978	3.722
1979	3.834
1980	3.947
1981	4.161
1982	4.387
1983	4.516
1984	4.655
1985	4.786
1986	5.092
1987	5.127
1988	5.244
1989	5.24
1990	4.975
1991	4.412
1992	3.915
1993	3.74
1994	3.78
1995	3.978
1996	4.038
1997	4.172
1998	4.294
1999	4.407
2000	4.424
2001	4.521
2002	4.695
2003	4.978
2004	5.455
2005	5.796
2006	6.217
2007	6.757
2008	7.251
2009	7.029