Year Percent change (Units) 1980 -4.947 1981 -1.288 1982 2.645 1983 -9.856 1984 5.223 1985 0.867 1986 6.080 1987 4.801 1988 6.510 1989 -13.920 1990 6.468 1991 9.730 1992 6.060 1993 0.275 1994 -2.349 1995 3.952 1996 -0.198 1997 6.371 1998 0.294 1999 -5.970 2000 3.687 2001 3.394 2002 -8.856 2003 -7.755 2004 18.287 2005 10.318 2006 9.872 2007 8.754 2008 5.278 2009 -3.202 2010 -1.489 2011 4.176 2012 5.626 2013 1.343 2014 -3.894 2015 -6.221 2016 -17.040 2017 -15.671 2018 -19.655 2019 -27.670 2020 -29.995 2021 1.000 2022 8.000 2023 4.000 2024 4.000 2025 3.000