Year Percent 1989-01-01 2.4180099999999998 1990-01-01 2.4705300000000000 1991-01-01 2.5151200000000000 1992-01-01 3.0452300000000000 1993-01-01 2.4633200000000000 1994-01-01 3.6623900000000003 1995-01-01 4.1512600000000000 1996-01-01 4.5854099999999995 1997-01-01 11.1181000000000000 1998-01-01 27.8851000000000000 1999-01-01 33.8103000000000000 2000-01-01 37.1684000000000000 2001-01-01 33.7477000000000000 2002-01-01 19.1490000000000000 2003-01-01 15.4715000000000000 2004-01-01 16.7292000000000000 2005-01-01 18.4396000000000000 2006-01-01 24.4629000000000000 2007-01-01 43.5096000000000000 2008-01-01 43.0412000000000000 2009-01-01 23.9095000000000000 2010-01-01 20.1850000000000000 2011-01-01 18.9611000000000000 2012-01-01 13.8178000000000000 2013-01-01 14.6309999999999980 2014-01-01 18.6017000000000000