Year	Percent
1983-01-01	29.2048
1984-01-01	31.3530
1985-01-01	35.9269
1986-01-01	31.4968
1987-01-01	28.6524
1988-01-01	24.7110
1989-01-01	24.6552
1990-01-01	21.9852
1991-01-01	21.3251
1992-01-01	19.2438
1993-01-01	21.5756
1994-01-01	25.6003
1995-01-01	24.7772
1996-01-01	29.2455
1997-01-01	33.0278
1998-01-01	35.6531
1999-01-01	41.7245
2000-01-01	58.6578
2001-01-01	49.1475
2002-01-01	59.3170
2003-01-01	50.4560
2004-01-01	55.5216
2005-01-01	65.5009
2006-01-01	77.0597
2007-01-01	83.8077
2008-01-01	73.0781
2009-01-01	67.8765
2010-01-01	50.5756
2011-01-01	40.1879
2012-01-01	22.8858
2013-01-01	28.9636
2014-01-01	27.2183
2015-01-01	20.6340
2016-01-01	26.2497