Year	Years
1800	371.2
1900	325.7
1930	227.5
1950	109.6
1951	108
1952	105.2
1953	102.3
1954	99.28
1955	95.57
1956	92.43
1957	89.22
1958	85.95
1959	82.78
1960	79.1
1961	76.08
1962	73.11
1963	69.69
1964	66.85
1965	63.58
1966	60.86
1976	87.8
1977	84.2
1978	80.9
1979	77.7
1980	74.7
1981	71.8
1982	69
1983	66.3
1984	63.8
1985	61.3
1986	58.9
1987	56.6
1988	81.6
1989	52
1990	49.7
1991	47.4
1992	45.1
1993	42.8
1994	40.7
1995	38.6
1996	36.7
1997	34.9
1998	33.3
1999	31.7
2000	30.1
2001	28.6
2002	27.2
2003	25.9
2004	24.6
2005	23.4
2006	22.2
2007	21.1
2008	20.1
2009	19.1
2010	18.1
2011	17.2
2012	16.4
2013	15.6