Year	Percent
1996-01-01	33.7574
1997-01-01	31.9270
1998-01-01	28.2681
1999-01-01	36.8709
2000-01-01	53.9082
2001-01-01	35.8256
2002-01-01	44.7965
2003-01-01	38.4011
2004-01-01	70.3217
2005-01-01	52.7477
2006-01-01	40.7357
2007-01-01	40.3115
2008-01-01	39.5444
2009-01-01	36.4124
2010-01-01	44.7896
2011-01-01	33.9473
2012-01-01	21.7139
2013-01-01	16.9189
2014-01-01	13.8665
2015-01-01	13.9822
2016-01-01	16.1573