Year	Percent
1980-01-01	3.3591800000000003
1981-01-01	3.9140699999999997
1982-01-01	3.8129199999999996
1983-01-01	3.9218100000000000
1984-01-01	3.7988199999999996
1985-01-01	4.8009600000000000
1986-01-01	5.6901699999999990
1987-01-01	7.0945399999999990
1988-01-01	7.9627300000000005
1989-01-01	8.6798000000000000
1990-01-01	8.4095300000000000
1991-01-01	8.7840200000000000
1992-01-01	8.2930300000000000
1993-01-01	10.0740000000000000
1994-01-01	12.2576000000000000
1995-01-01	12.3903000000000000
1996-01-01	12.4106000000000000
1997-01-01	12.9573000000000000
1998-01-01	15.6476000000000000
1999-01-01	15.1261000000000000
2000-01-01	15.1637000000000000
2001-01-01	15.9025000000000000
2002-01-01	20.0107000000000000
2003-01-01	23.4662000000000000
2004-01-01	22.8781000000000000
2005-01-01	21.9089000000000000
2006-01-01	24.3376000000000000
2007-01-01	24.3769000000000000
2008-01-01	24.5504000000000000
2009-01-01	27.2838000000000000
2010-01-01	26.0565000000000000
2011-01-01	23.9525000000000000
2012-01-01	24.8316000000000000
2013-01-01	26.0034000000000000
2014-01-01	23.2908000000000000
2015-01-01	24.2022000000000000
2016-01-01	24.4181000000000000