Year Percent change 1980 -7.821 1981 9.94 1982 -2.262 1983 -63.156 1984 -74.252 1985 528.745 1986 126.56 1987 -5.382 1988 35.066 1989 -19.14 1990 17.853 1991 3.24 1992 18.933 1993 2.606 1994 2.456 1995 8.984 1996 -3.244 1997 12.979 1998 -4.733 1999 -17.861 2000 7.563 2001 3.023 2002 -12.047 2003 -4.815 2004 18.364 2005 17.238 2006 10.93 2007 15.104 2008 14.65 2009 -1.258 2010 1.622 2011 25.838 2012 3.516 2013 -10.368 2014 -15.881 2015 -0.059 2016 -18.505 2017 2.749 2018 7.415 2019 7.029 2020 7.686 2021 5.265 2022 4.011 2023 4.132 2024 4.283