Year Percent change 1980 -10.661 1981 14.805 1982 2.707 1983 6.451 1984 17.286 1985 5.971 1986 -8.582 1987 1.509 1988 14.061 1989 -3.567 1990 21.049 1991 1.605 1992 -6.634 1993 1.411 1994 3.574 1995 -0.964 1996 -1.942 1997 5.508 1998 1.228 1999 10.145 2000 4.529 2001 6.27 2002 9.704 2003 -9.954 2004 12.945 2005 0.839 2006 -13.404 2007 22.189 2008 21.543 2009 -19.533 2010 38.184 2011 9.51 2012 20.762 2013 16.281 2014 11.864 2015 7.702 2016 7.99 2017 11.703 2018 13.244 2019 5.576 2020 6.983 2021 2.891 2022 7.368 2023 8.149 2024 5.796