Year	Percent
1983-01-01	24.2091
1984-01-01	25.9658
1985-01-01	30.0464
1986-01-01	24.9245
1987-01-01	24.1292
1988-01-01	17.9253
1989-01-01	17.4312
1990-01-01	16.3652
1991-01-01	16.0257
1992-01-01	14.7605
1993-01-01	14.5468
1994-01-01	14.8995
1995-01-01	13.6129
1996-01-01	11.5937
1997-01-01	15.5566
1998-01-01	14.7227
1999-01-01	21.1640
2000-01-01	24.9803
2001-01-01	23.0184
2002-01-01	28.0763
2003-01-01	24.3373
2004-01-01	23.9376
2005-01-01	22.0506
2006-01-01	23.5108
2007-01-01	22.7033
2008-01-01	27.4812
2009-01-01	30.8965
2010-01-01	29.0140
2011-01-01	29.0370
2012-01-01	34.5324
2013-01-01	34.7999
2014-01-01	31.0129
2015-01-01	30.0651
2016-01-01	30.3677