Year Percent change (Units) 1980 -2.253 1981 -3.877 1982 -2.071 1983 -0.616 1984 4.306 1985 10.294 1986 0.762 1987 4.875 1988 5.326 1989 10.286 1990 7.455 1991 2.760 1992 7.173 1993 7.303 1994 -2.437 1995 0.485 1996 9.998 1997 12.194 1998 2.467 1999 1.872 2000 4.253 2001 -2.271 2002 1.213 2003 -5.887 2004 -2.850 2005 9.006 2006 9.406 2007 10.418 2008 -2.096 2009 -1.095 2010 6.321 2011 5.684 2012 3.820 2013 6.403 2014 4.717 2015 8.913 2016 12.118 2017 6.957 2018 4.937 2019 5.513 2020 -11.741 2021 0.554 2022 14.978 2023 3.679 2024 3.229 2025 3.787 2026 3.762 2027 3.696 2028 3.643 2029 3.590