Year	per person
1800	1.147
1820	1.147
1905	1.41
1906	1.421
1907	1.486
1908	1.539
1909	1.589
1910	1.647
1911	1.695
1912	1.744
1913	1.785
1914	1.806
1915	1.843
1916	1.89
1917	1.919
1918	1.976
1919	2.089
1920	2.177
1921	2.246
1922	2.34
1923	2.429
1924	2.504
1925	2.574
1926	2.753
1927	2.93
1928	3.069
1929	3.1
1930	3.037
1931	2.952
1932	3.112
1933	3.25
1934	3.416
1935	3.458
1936	3.6
1937	3.614
1938	3.805
1939	3.937
1940	3.917
1941	3.878
1942	3.782
1943	3.696
1944	3.847
1945	3.925
1946	4.197
1947	4.248
1948	4.255
1949	4.512
1950	4.579
1951	4.56
1952	4.702
1953	4.79
1954	4.978
1955	5.014
1956	5.09
1957	5.096
1958	5.027
1959	5.223
1960	5.261
1961	5.359
1962	5.466
1963	5.469
1964	5.629
1965	5.682
1966	5.829
1967	5.874
1968	6.076
1969	6.297
1970	6.552
1971	6.789
1972	7.159
1973	7.49
1974	7.801
1975	7.868
1976	8.128
1977	8.368
1978	8.981
1979	9.349
1980	9.604
1981	9.703
1982	9.644
1983	9.663
1984	9.804
1985	9.943
1986	10.35
1987	10.75
1988	11.07
1989	11.28
1990	11.63
1991	11.67
1992	11.94
1993	12.38
1994	12.77
1995	13.19
1996	13.21
1997	13.42
1998	13.25
1999	12.46
2000	12.61
2001	12.58
2002	12.62
2003	12.91
2004	13.33
2005	13.83
2006	14.61
2007	15.53
2008	15.72
2009	15.55