Year Percent 1982-01-01 1.3952900000000000 1983-01-01 1.6172600000000001 1984-01-01 2.1075900000000000 1985-01-01 2.5553900000000000 1986-01-01 2.9580599999999997 1987-01-01 3.4166199999999995 1988-01-01 3.5965100000000000 1989-01-01 3.4599400000000000 1990-01-01 3.1178400000000000 1991-01-01 2.9576400000000000 1992-01-01 2.8499100000000000 1993-01-01 2.8171000000000000 1994-01-01 2.5804400000000003 1995-01-01 2.4937300000000000 1996-01-01 3.4252300000000004 1997-01-01 3.7976000000000000 1998-01-01 4.2286199999999990 1999-01-01 3.2388900000000000 2000-01-01 3.0678000000000000 2001-01-01 2.2679500000000000 2002-01-01 1.4520300000000000 2003-01-01 1.1369500000000000 2004-01-01 0.9647280000000000 2005-01-01 0.8038310000000001 2006-01-01 0.7394830000000000 2007-01-01 0.6529699999999999 2008-01-01 0.5373470000000000 2009-01-01 0.8175910000000000 2010-01-01 1.3154900000000000