Year Percent change 1981 -6.057 1982 13.111 1983 -25.081 1984 -21.294 1985 76.225 1986 51.084 1987 3.612 1988 -12.146 1989 -15.761 1990 37.291 1991 -19.011 1992 9.656 1993 18.6 1994 -59.412 1995 61.014 1996 35.714 1997 -12.052 1998 58.547 1999 -11.355 2000 -22.746 2001 10.164 2002 16.672 2003 40.532 2004 24.792 2005 8.96 2006 8.834 2007 25.692 2008 35.951 2009 -10.746 2010 34.102 2011 56.157 2012 25.651 2013 45.258 2014 -15.408 2015 -2.18 2016 28.031 2017 34.611 2018 12.695 2019 3.568 2020 6.706 2021 9.739 2022 8.731 2023 8.29 2024 15.304