Year	per person
1800	1.754
1820	1.754
1913	2.709
1950	4.25
1951	4.336
1952	4.316
1953	4.319
1954	4.416
1955	4.415
1956	4.427
1957	4.461
1958	4.454
1959	4.583
1960	4.74
1961	5.665
1962	5.546
1963	6.195
1964	5.604
1965	5.636
1966	5.305
1967	5.428
1968	4.962
1969	5.13
1970	5.027
1971	5.201
1972	5.648
1973	6.281
1974	6.862
1975	6.775
1976	7.768
1977	8.138
1978	8.301
1979	8.437
1980	7.453
1981	7.767
1982	8.088
1983	8.037
1984	8.332
1985	8.83
1986	9.619
1987	10.49
1988	11.1
1989	11.48
1990	12.17
1991	12.81
1992	13.29
1993	14.03
1994	14.51
1995	14.88
1996	15.5
1997	16.28
1998	17.11
1999	17.87
2000	18.18
2001	19.3
2002	19.78
2003	20.98
2004	21.78
2005	22.27
2006	22.96
2007	24.05
2008	24.85
2009	25.03