Year Percent 1991 79.3861 1992 568.8073 1993 1391.16654 1994 4107.29677 1995 161.16392 1996 19.59177 1997 17.73599 1998 10.6985 1999 0.0538 2000 -1.37368 2001 4.06914 2002 2.36979 2003 4.5611 2004 6.30953 2005 3.23984 2006 4.61986 2007 4.23277 2008 5.98956 2009 2.55694 2010 7.76872 2011 4.28155 2012 5.3458 2013 3.36682 2014 2.30918 2015 1.21391 2016 0.26858 2017 2.23157