Year Percent change (Units) 1980 -6.000 1981 -10.000 1982 -4.846 1983 5.600 1984 -0.366 1985 3.862 1986 3.494 1987 2.302 1988 3.285 1989 3.812 1990 -7.171 1991 -7.005 1992 2.033 1993 4.287 1994 5.239 1995 6.728 1996 6.239 1997 7.086 1998 4.982 1999 4.524 2000 4.260 2001 1.205 2002 1.443 2003 3.498 2004 4.983 2005 3.507 2006 6.131 2007 7.062 2008 4.200 2009 2.832 2010 2.935 2011 5.042 2012 1.545 2013 0.857 2014 3.837 2015 4.383 2016 2.954 2017 5.140 2018 5.945 2019 4.450 2020 -2.020 2021 6.935 2022 5.260 2023 0.160 2024 3.068 2025 3.476 2026 3.296 2027 2.996 2028 2.969 2029 3.011