Year	Percent
1960-01-01	219.42900000000000
1961-01-01	230.77400000000000
1962-01-01	242.02400000000000
1963-01-01	282.08200000000000
1964-01-01	338.88199999999995
1965-01-01	324.13700000000000
1966-01-01	321.83299999999997
1967-01-01	260.93000000000000
1968-01-01	169.73100000000000
1969-01-01	132.96000000000000
1970-01-01	106.16200000000000
1971-01-01	84.39820000000000
1972-01-01	65.33190000000000
1973-01-01	54.83040000000000
1974-01-01	40.18540000000000
1975-01-01	29.35040000000000
1976-01-01	28.96140000000000
1977-01-01	29.62450000000000
1978-01-01	27.80200000000000
1979-01-01	30.82030000000000
1980-01-01	32.65230000000000
1981-01-01	29.32140000000000
1982-01-01	29.36380000000000
1983-01-01	30.27500000000000
1984-01-01	28.28970000000000
1985-01-01	24.69320000000000
1986-01-01	23.00260000000000
1987-01-01	24.74140000000000
1988-01-01	27.84060000000000
1989-01-01	30.84330000000000
1990-01-01	31.59110000000000
1991-01-01	34.19160000000000
1992-01-01	38.25870000000000
1993-01-01	36.82210000000000
1994-01-01	34.59970000000000
1995-01-01	36.01420000000000
1996-01-01	36.30800000000000
1997-01-01	35.00510000000000
1998-01-01	32.85680000000000
1999-01-01	28.71700000000000
2000-01-01	24.18260000000000
2001-01-01	19.40560000000000
2002-01-01	16.12630000000000
2003-01-01	16.75950000000000
2004-01-01	20.87490000000000
2005-01-01	27.82010000000000
2006-01-01	32.74010000000000
2007-01-01	33.81160000000000
2008-01-01	34.11980000000000
2009-01-01	36.26870000000000
2010-01-01	40.23450000000000