Year Percent change 1980 18.724 1981 13.269 1982 -33.994 1983 -17.671 1984 12.002 1985 -9.462 1986 7.904 1987 18.61 1988 12.793 1989 25.038 1990 5.8 1991 7.129 1992 21.812 1993 13.97 1994 10.15 1995 25.158 1996 11.867 1997 13.215 1998 6.87 1999 -9.791 2000 10.352 2001 5.316 2002 1.847 2003 5.697 2004 19.295 2005 18.371 2006 11.765 2007 13.769 2008 11.576 2009 -16.682 2010 25.602 2011 15.418 2012 5.108 2013 2.137 2014 -6.477 2015 -1.193 2016 0.891 2017 4.723 2018 7.617 2019 1.614 2020 2.414 2021 3.848 2022 3.488 2023 3.377 2024 3.255