Year	per person
1800	2.978
1820	3.04
1870	3.823
1890	5.38
1900	5.757
1910	6.745
1913	6.745
1920	6.581
1921	6.646
1922	6.744
1923	6.995
1924	7.391
1925	7.645
1926	8.063
1927	7.82
1928	8.387
1929	8.706
1930	8.414
1931	8.046
1932	7.197
1933	7.319
1934	7.488
1935	7.274
1936	8.106
1937	8.127
1938	8.657
1939	9.01
1947	8.395
1948	9.882
1949	10.71
1950	9.898
1951	10.15
1952	9.244
1953	10.48
1954	10.93
1955	11.47
1956	11.12
1957	12.86
1958	13.27
1959	14.77
1960	15.55
1961	16.09
1962	16.23
1963	17.75
1964	19.27
1965	19.6
1966	20.45
1967	20.63
1968	20.88
1969	23.04
1970	23.96
1971	26.49
1972	27.16
1973	27.83
1974	31.14
1975	30.87
1976	31.52
1977	33.5
1978	35.04
1979	37.13
1980	38.7
1981	39.15
1982	39.18
1983	39.3
1984	40.07
1985	40.18
1986	41.62
1987	40.96
1988	40.21
1989	39.52
1990	36.5
1991	33.12
1992	31.17
1993	31.93
1994	33.51
1995	34.77
1996	35.95
1997	37.63
1998	38.92
1999	40.93
2000	42.54
2001	43.79
2002	45.31
2003	46.5
2004	48.49
2005	50.45
2006	53.19
2007	56.83
2008	58.73
2009	54.34