Year Percent change 1980 -15.913 1981 -32.025 1982 0.614 1983 -1.729 1984 -7.703 1985 -3.383 1986 16.73 1987 -26.272 1988 20.77 1989 20.199 1990 19.981 1991 -19.156 1992 -6.95 1993 -6.959 1994 -6.433 1995 26.051 1996 -15.456 1997 2.87 1998 -7.447 1999 2.279 2000 2.143 2001 -5.156 2002 -16.385 2003 29.391 2004 10.337 2005 9.104 2006 9.179 2007 3.44 2008 -6.528 2009 -7.437 2010 -0.677 2011 -68.933 2012 217.17 2013 -23.911 2014 -54.737 2015 4.47 2016 3.934 2017 72.205 2018 34.68 2019 -23.136 2020 -4.908 2021 -3.983 2022 -0.951 2023 0.051 2024 0.167