Year Percent change (Units) 1980 -6.825 1981 12.164 1982 -1.054 1983 3.715 1984 0.155 1985 11.784 1986 3.250 1987 5.503 1988 5.031 1989 1.349 1990 3.458 1991 5.781 1992 1.007 1993 -6.236 1994 -3.829 1995 -7.919 1996 -8.001 1997 0.413 1998 4.752 1999 1.164 2000 1.781 2001 1.665 2002 2.353 2003 2.469 2004 3.766 2005 4.370 2006 5.414 2007 3.452 2008 4.862 2009 3.813 2010 5.124 2011 4.033 2012 4.447 2013 4.924 2014 4.241 2015 -3.900 2016 -0.600 2017 0.500 2018 1.610 2019 1.842 2020 0.335 2021 3.119 2022 1.827 2023 2.659 2024 4.282 2025 5.350 2026 6.045 2027 6.004 2028 5.529 2029 5.012