Year Percent change 1980 21.258 1981 21.614 1982 6.003 1983 2.658 1984 5.228 1985 -24.039 1986 22.11 1987 -4.87 1988 -0.691 1989 5.091 1990 -34.132 1991 0.32 1992 -38.605 1993 39.092 1994 -32.71 1995 1.457 1996 9.964 1997 15.277 1998 30.857 1999 8.568 2000 -10.145 2001 1.263 2002 12.406 2003 12.516 2004 6.556 2005 48.742 2006 -14.183 2007 9.603 2008 21.827 2009 -10.042 2010 26.639 2011 31.124 2012 -6.168 2013 -7.71 2014 4.521 2015 14.893 2016 3.021 2017 -3.254 2018 0.561 2019 -8.346 2020 -3.93 2021 -3.291 2022 0.585 2023 4.561 2024 3.734