Year Percent change (Units) 1986 -2.715 1987 2.009 1988 1.097 1989 -1.074 1990 1.089 1991 3.146 1992 4.759 1993 0.305 1994 3.145 1995 4.479 1996 2.878 1997 -1.471 1998 -0.559 1999 3.052 2000 2.849 2001 2.744 2002 3.872 2003 2.904 2004 0.504 2005 0.388 2006 4.398 2007 0.154 2008 -1.939 2009 -1.765 2010 2.599 2011 3.744 2012 0.913 2013 -2.125 2014 -2.508 2015 -0.405 2016 -2.465 2017 1.329 2018 0.052 2019 3.869 2020 1.134 2021 -1.591 2022 -1.628 2023 1.407 2024 2.385 2025 2.519 2026 2.918 2027 3.055 2028 3.060 2029 3.080