Year Percent 1991-01-01 83.78378378378380 1992-01-01 299.50980392156900 1993-01-01 1378.52760736196000 1994-01-01 949.79253112033200 1995-01-01 2666.45059288538000 1996-01-01 4145.10598220638000 1997-01-01 219.17672117297400 1998-01-01 107.28482152829800 1999-01-01 248.19590241286800 2000-01-01 324.99687160132100 2001-01-01 152.56102246929900 2002-01-01 108.89743608942900 2003-01-01 98.22414365733040 2004-01-01 43.54210675196870 2005-01-01 22.95351385139410 2006-01-01 13.30521017800310 2007-01-01 12.25149744594870 2008-01-01 12.47582913263980 2009-01-01 13.73028392884090 2010-01-01 14.46965649325740 2011-01-01 13.48246792185110 2012-01-01 10.27790492188390 2013-01-01 8.77781429332619 2014-01-01 7.28038730361125 2015-01-01 10.27804606610700 2016-01-01 32.37773406963780 2017-01-01 31.69168614064810