Year Percent change 1980 15.631 1981 10.008 1982 -2.087 1983 9.479 1984 14.805 1985 6.431 1986 13.558 1987 31.749 1988 26.768 1989 8.925 1990 11.536 1991 19.133 1992 22.306 1993 13.031 1994 13.671 1995 13.801 1996 4.313 1997 7.262 1998 -6.942 1999 -0.055 2000 20.192 2001 -1.45 2002 8.53 2003 15.48 2004 15.182 2005 9.166 2006 9.409 2007 9.852 2008 3.733 2009 -6.954 2010 19.88 2011 6.663 2012 4.575 2013 9.919 2014 1.475 2015 -2.673 2016 0.708 2017 7.272 2018 4.86 2019 2.217 2020 2.995 2021 3.43 2022 3.691 2023 3.75 2024 3.826