Year	Percent
1972-01-01	0.49571000000000004
1973-01-01	1.00483000000000000
1974-01-01	0.87404500000000010
1975-01-01	0.84957199999999990
1976-01-01	0.85971900000000000
1977-01-01	1.12638000000000000
1978-01-01	1.78502000000000000
1979-01-01	2.01285000000000000
1980-01-01	1.63753000000000000
1981-01-01	1.49173000000000000
1982-01-01	3.74938000000000040
1983-01-01	7.29566000000000100
1984-01-01	9.43921000000000100
1985-01-01	17.28520000000000000
1986-01-01	21.11810000000000000
1987-01-01	20.54580000000000000
1988-01-01	17.92650000000000000
1989-01-01	15.65570000000000000
1990-01-01	14.56020000000000000
1991-01-01	13.59710000000000000
1992-01-01	9.05739000000000000
1993-01-01	7.31301000000000000
1994-01-01	6.95910000000000000
1995-01-01	7.49902000000000000
1996-01-01	9.11011000000000000
1997-01-01	12.48130000000000000
1998-01-01	16.69860000000000000
1999-01-01	18.47280000000000000
2000-01-01	16.79500000000000000
2001-01-01	18.53340000000000000
2002-01-01	22.66940000000000000
2003-01-01	20.78720000000000000
2004-01-01	22.80730000000000000
2005-01-01	19.84200000000000000
2006-01-01	19.32190000000000000
2007-01-01	16.46620000000000000
2008-01-01	14.01610000000000000
2009-01-01	16.39050000000000000
2010-01-01	15.65980000000000000
2011-01-01	13.84790000000000000
2012-01-01	16.09990000000000000
2013-01-01	16.70240000000000000
2014-01-01	16.33160000000000000
2015-01-01	20.25580000000000000
2016-01-01	21.52830000000000000