Year	Percent
1980-01-01	5.7746400000000000
1981-01-01	5.4937400000000000
1982-01-01	6.2751700000000000
1983-01-01	6.3204100000000000
1984-01-01	5.9273500000000000
1985-01-01	5.4757400000000000
1986-01-01	6.1153000000000000
1987-01-01	5.1483800000000000
1988-01-01	5.2106000000000000
1989-01-01	5.1045600000000000
1990-01-01	4.6744200000000000
1991-01-01	5.1660900000000005
1992-01-01	6.4138199999999990
1993-01-01	6.6459100000000010
1994-01-01	5.9421100000000000
1995-01-01	5.2334600000000000
1996-01-01	5.1676699999999990
1997-01-01	5.6535000000000000
1998-01-01	5.8148400000000000
1999-01-01	6.0227600000000000
2000-01-01	6.6802500000000000
2001-01-01	13.7003000000000000
2002-01-01	14.8943000000000000
2003-01-01	14.9321000000000000
2004-01-01	15.4540000000000000
2005-01-01	15.2464000000000000
2006-01-01	14.5527000000000000
2007-01-01	14.6314000000000000
2008-01-01	15.1733000000000000
2009-01-01	15.8886000000000000
2010-01-01	15.4291000000000000
2011-01-01	15.6325000000000000
2012-01-01	15.3925000000000000
2013-01-01	16.9759000000000000
2014-01-01	18.8329000000000000
2015-01-01	17.7923000000000000
2016-01-01	17.7295000000000000