Year Percent change (Units) 1980 7.240 1981 4.045 1982 2.442 1983 1.652 1984 2.298 1985 1.650 1986 -0.225 1987 0.754 1988 1.060 1989 2.601 1990 3.621 1991 2.797 1992 0.981 1993 1.101 1994 0.809 1995 -0.575 1996 0.526 1997 2.078 1998 0.535 1999 -1.013 2000 -0.766 2001 -0.910 2002 -0.536 2003 -0.308 2004 0.527 2005 -0.760 2006 0.368 2007 0.512 2008 1.073 2009 -2.000 2010 -0.255 2011 -0.302 2012 -0.245 2013 1.397 2014 2.551 2015 0.197 2016 0.267 2017 0.549 2018 0.868 2019 0.510 2020 -0.916 2021 0.513 2022 3.871 2023 2.921 2024 2.012 2025 1.994 2026 2.004 2027 2.004 2028 2.004 2029 2.004