Year Percent change 1981 -16.967 1982 -28.292 1983 -19.389 1984 -14.481 1985 7.418 1986 28.664 1987 16.461 1988 -32.295 1989 19.042 1990 32.51 1991 -12.688 1992 -2.628 1993 31.932 1994 3.63 1995 0.934 1996 28.341 1997 -61.368 1998 13.704 1999 42.934 2000 29.181 2001 16.993 2002 18.996 2003 5.246 2004 -18.949 2005 11.039 2006 -6.707 2007 -4 2008 7.028 2009 14.139 2010 62.114 2011 86.006 2012 17.205 2013 -6.446 2014 29.207 2015 -25.49 2016 -19.943 2017 18.845 2018 -4.577 2019 9.805 2020 4.681 2021 3.495 2022 2.327 2023 6.54 2024 4.278