Year Percent change (Units) 1980 15.578 1981 14.549 1982 14.416 1983 12.174 1984 11.280 1985 8.815 1986 8.795 1987 5.248 1988 4.837 1989 6.791 1990 6.722 1991 5.934 1992 7.145 1993 4.569 1994 4.718 1995 4.674 1996 3.599 1997 1.877 1998 1.764 1999 2.235 2000 3.484 2001 2.825 2002 3.590 2003 3.103 2004 3.054 2005 3.384 2006 3.561 2007 2.843 2008 4.131 2009 -0.239 2010 2.043 2011 3.050 2012 2.436 2013 1.530 2014 -0.190 2015 -0.629 2016 -0.337 2017 2.036 2018 1.736 2019 0.780 2020 -0.337 2021 3.008 2022 8.323 2023 3.400 2024 2.674 2025 2.361 2026 1.889 2027 1.800 2028 1.800 2029 1.800