Year Percent change 1980 -9 1981 11.2 1982 0.3 1983 13.3 1984 15.5 1985 6.1 1986 8.1 1987 20.9 1988 16.7 1989 13.33 1990 12.517 1991 20.126 1992 3.751 1993 7.717 1994 21.672 1995 21.165 1996 14.323 1997 1.576 1998 -26.788 1999 29.787 2000 22.618 2001 -4.575 2002 15.109 2003 11.728 2004 11.035 2005 6.891 2006 12.466 2007 10.555 2008 3.009 2009 -7.052 2010 19.105 2011 17.569 2012 1.905 2013 1.318 2014 0.527 2015 0.716 2016 3.325 2017 7.424 2018 1.894 2019 3.044 2020 2.945 2021 4.034 2022 3.992 2023 3.96 2024 3.995