Year	Percent
1996-01-01	29.3049
1997-01-01	30.9862
1998-01-01	21.1864
1999-01-01	25.0726
2000-01-01	35.0522
2001-01-01	27.5749
2002-01-01	36.9364
2003-01-01	38.1685
2004-01-01	31.4132
2005-01-01	31.2632
2006-01-01	25.7213
2007-01-01	28.9209
2008-01-01	28.7480
2009-01-01	28.8476
2010-01-01	30.4441
2011-01-01	27.6160
2012-01-01	23.2505
2013-01-01	20.0657
2014-01-01	17.7342
2015-01-01	19.7673
2016-01-01	16.9007