Year	per person
1800	3.09
1820	3.09
1913	5.702
1938	13.79
1950	21.08
1960	30.01
1961	31.59
1962	33.15
1963	34.83
1964	36.64
1965	38.62
1966	40.3
1967	42.36
1968	44.2
1969	46.53
1970	42.59
1971	42.17
1972	39.81
1973	41.98
1974	34.28
1975	28.64
1976	29.51
1977	31.54
1978	35.24
1979	43.5
1980	45.33
1981	43.08
1982	44.81
1983	46.85
1984	46.98
1985	47.96
1986	48.3
1987	49.21
1988	49.45
1989	49.71
1990	48.04
1991	45.18
1992	42.62
1993	41.93
1994	42.44
1995	43.51
1996	44.58
1997	46.03
1998	48.41
1999	49.61
2000	49.84
2001	49.56
2002	50.02
2003	49.88
2004	49.88
2005	50.48
2006	51.91
2007	51.59
2008	50.06
2009	47.22