Year	per person
1800	2.202
1820	2.202
1913	4.063
1950	7.021
1970	10.87
1971	11.52
1972	12.07
1973	12.63
1974	13.07
1975	11.87
1976	13.06
1977	14.52
1978	15.41
1979	14.54
1980	13.26
1981	14.07
1982	13.29
1983	12.55
1984	12.1
1985	13.58
1986	13.18
1987	12.08
1988	13.01
1989	13.48
1990	12.86
1991	13.07
1992	13.1
1993	12.33
1994	11.84
1995	12.08
1996	12.11
1997	12.26
1998	12.51
1999	12.08
2000	12.45
2001	13.07
2002	13.31
2003	14.14
2004	15.09
2005	15.86
2006	16.28
2007	16.93
2008	17.75
2009	17.98