Year Percent change (Units) 1980 19.700 1981 12.700 1982 5.300 1983 3.700 1984 0.795 1985 2.440 1986 1.848 1987 2.452 1988 3.885 1989 5.379 1990 5.779 1991 5.787 1992 4.018 1993 3.380 1994 5.054 1995 5.795 1996 5.823 1997 5.630 1998 7.962 1999 0.236 2000 1.700 2001 1.610 2002 0.660 2003 1.813 2004 2.812 2005 4.467 2006 4.712 2007 2.167 2008 5.485 2009 -0.870 2010 3.299 2011 3.811 2012 3.012 2013 2.185 2014 1.894 2015 -0.899 2016 0.188 2017 0.665 2018 1.065 2019 0.706 2020 -0.847 2021 1.231 2022 6.077 2023 1.228 2024 0.700 2025 1.209 2026 1.688 2027 2.000 2028 2.000 2029 2.000