Year	Percent
1975-01-01	0.13150200000000000
1976-01-01	0.13115500000000000
1977-01-01	0.11553400000000000
1978-01-01	0.09538200000000001
1979-01-01	0.09124900000000000
1980-01-01	0.08069900000000000
1981-01-01	0.08133200000000000
1982-01-01	0.08694400000000001
1983-01-01	0.17804900000000000
1984-01-01	0.26184500000000000
1985-01-01	1.31628000000000000
1986-01-01	2.29607000000000030
1987-01-01	2.10040000000000000
1988-01-01	3.09550000000000000
1989-01-01	8.22463999999999900
1990-01-01	10.28640000000000000
1991-01-01	7.75672000000000000
1992-01-01	8.46849000000000000
1993-01-01	11.93600000000000000
1994-01-01	14.81100000000000000
1995-01-01	15.04540000000000000
1996-01-01	15.78180000000000000
1997-01-01	21.21070000000000000
1998-01-01	31.19800000000000000
1999-01-01	33.86920000000000000
2000-01-01	42.00550000000000000
2001-01-01	46.81040000000000000
2002-01-01	28.86750000000000000
2003-01-01	19.10660000000000000
2004-01-01	23.25430000000000000
2005-01-01	47.29630000000000000
2006-01-01	58.54290000000000000
2007-01-01	68.10030000000000000
2008-01-01	67.69610000000000000
2009-01-01	55.19900000000000000
2010-01-01	45.01760000000000000
2011-01-01	44.55470000000000000
2012-01-01	38.41740000000000000