Year	Percent
1984-01-01	37.588900000000000
1985-01-01	38.628500000000000
1986-01-01	42.846100000000000
1987-01-01	43.054700000000000
1988-01-01	45.558000000000000
1989-01-01	47.017300000000000
1990-01-01	46.167800000000000
1991-01-01	43.361000000000004
1992-01-01	41.087700000000000
1993-01-01	40.306500000000000
1994-01-01	37.443600000000000
1995-01-01	40.226200000000000
1996-01-01	43.629500000000000
1997-01-01	43.260800000000000
1998-01-01	44.075700000000000
1999-01-01	28.391800000000000
2000-01-01	29.864200000000000
2001-01-01	28.476300000000000
2002-01-01	24.659300000000000
2003-01-01	22.638600000000000
2004-01-01	21.188700000000000
2005-01-01	20.006600000000000
2006-01-01	19.384500000000000
2007-01-01	20.245000000000000
2008-01-01	22.515100000000000
2009-01-01	26.733600000000000
2010-01-01	30.984100000000000
2011-01-01	30.521100000000000
2012-01-01	28.440600000000000
2013-01-01	29.244900000000000
2014-01-01	29.663800000000000
2015-01-01	28.921200000000000
2016-01-01	27.662800000000000