Year	per person
1800	2.261
1820	2.337
1913	6.92
1970	39.53
1971	39.91
1972	41.2
1973	44.02
1974	46.25
1975	44.91
1976	47.51
1977	47.94
1978	48.61
1979	50.57
1980	51.46
1981	51.16
1982	50.69
1983	50.66
1984	51.69
1985	52.52
1986	53.4
1987	54.49
1988	56.14
1989	57.38
1990	57.87
1991	58.01
1992	57.69
1993	61.92
1994	65.45
1995	70.77
1996	73.6
1997	74.87
1998	79.93
1999	86.29
2000	86.85
2001	89.84
2002	87.87
2003	88.94
2004	90.86
2005	91.21
2006	93.4
2007	95.72
2008	96.88