Year Percent change 1980 2.894 1981 4.127 1982 0.063 1983 -0.474 1984 6.346 1985 5.456 1986 2.448 1987 4.893 1988 4.253 1989 4.626 1990 1.502 1991 -1.009 1992 2.565 1993 3.902 1994 4.892 1995 2.843 1996 4.159 1997 4.558 1998 4.723 1999 4.446 2000 3.038 2001 2.601 2002 4.176 2003 2.671 2004 4.28 2005 2.878 2006 2.819 2007 4.368 2008 2.675 2009 1.884 2010 2.386 2011 2.765 2012 3.875 2013 2.137 2014 2.642 2015 2.461 2016 2.779 2017 2.382 2018 2.811 2019 2.072 2020 2.759 2021 2.762 2022 2.641 2023 2.65 2024 2.638