Year Percent 1995-01-01 4.89732453075000 1996-01-01 5.30136145225000 1997-01-01 5.64717785650000 1998-01-01 7.98651111575000 1999-01-01 7.82450712250000 2000-01-01 8.06821917350000 2001-01-01 7.43039797900000 2002-01-01 7.58076115575000 2003-01-01 7.36339999350000 2004-01-01 7.86953015700000 2005-01-01 8.08433372875000 2006-01-01 6.91531308700000 2007-01-01 5.88549356025000 2008-01-01 4.58999526375000 2009-01-01 5.58471656925000 2010-01-01 5.24139934650000 2011-01-01 4.58714296050000 2012-01-01 5.11666666666667 2013-01-01 5.01666666666667 2014-01-01 4.28333333333333 2015-01-01 4.37500000000000 2016-01-01 4.45833333333333 2017-01-01 3.80000000000000