Year	Years
1800	448
1900	447
1922	231.5
1923	197.8
1924	160.4
1925	209.1
1926	164.1
1927	177.2
1928	142
1929	131.2
1930	95.24
1931	117.2
1932	124.1
1933	115.4
1934	110.3
1935	87.19
1936	95.24
1937	76.57
1938	79.68
1939	71.9
1940	79.68
1941	75.01
1942	78.12
1943	56.87
1944	45.49
1945	45.49
1946	40.06
1947	37.32
1948	45.49
1949	68.83
1950	61.29
1951	52.53
1952	55.42
1953	51.09
1954	49.67
1955	46.87
1956	51.09
1957	49.67
1958	44.11
1959	40.06
1960	40.06
1970	29.34
1973	29
1974	29.1
1975	26.2
1976	23.8
1977	21.8
1978	20.2
1979	19
1980	18
1981	17.3
1982	16.6
1983	15.9
1984	15.2
1985	14.4
1986	13.7
1987	13.1
1988	12.5
1989	12.1
1990	11.6
1991	11.1
1992	10.5
1993	9.8
1994	9.2
1995	8.7
1996	8.2
1997	7.8
1998	7.5
1999	7.2
2000	6.9
2001	6.6
2002	6.4
2003	6.1
2004	5.9
2005	5.6
2006	5.3
2007	5.1
2008	4.9
2009	4.7
2010	4.5
2011	4.3
2012	4.2
2013	4