Year	Percent
1987-01-01	6.74607
1988-01-01	6.71490
1989-01-01	8.37032
1990-01-01	12.46570
1991-01-01	14.01300
1992-01-01	14.92360
1993-01-01	18.10120
1994-01-01	21.36900
1995-01-01	21.57450
1996-01-01	21.25580
1997-01-01	21.15630
1998-01-01	21.09280
1999-01-01	17.13730
2000-01-01	12.84640
2001-01-01	12.97870
2002-01-01	15.13840
2003-01-01	16.31210
2004-01-01	16.17410
2005-01-01	12.93490
2006-01-01	10.91490
2007-01-01	10.35460
2008-01-01	14.21790
2009-01-01	28.91060
2010-01-01	50.68730
2011-01-01	47.43490
2012-01-01	49.02920
2013-01-01	50.64270
2014-01-01	43.58260
2015-01-01	44.49530
2016-01-01	41.44820