Year Percent change 1980 11.4 1981 17.6 1982 6.5 1983 16.3 1984 15.6 1985 7.6 1986 12.3 1987 23.7 1988 15.3 1989 -4.068 1990 3.86 1991 13.83 1992 12.656 1993 8.359 1994 15.768 1995 22.845 1996 10.289 1997 19.24 1998 15.777 1999 16.391 2000 19.107 2001 -2.485 2002 15.967 2003 16.509 2004 20.224 2005 9.209 2006 13.39 2007 12.4 2008 6.022 2009 0.399 2010 13.494 2011 17.079 2012 4.386 2013 4.473 2014 1.089 2015 -0.581 2016 2.085 2017 3.754 2018 3.968 2019 2.339 2020 2.686 2021 3.827 2022 3.641 2023 3.498 2024 3.506