Year Percent change (Units) 1993 -9.400 1994 9.400 1995 8.100 1996 9.912 1997 60.576 1998 -16.845 1999 -33.379 2000 12.910 2001 14.043 2002 21.274 2003 3.446 2004 7.987 2005 8.393 2006 32.225 2007 36.350 2008 21.250 2009 -36.350 2010 33.000 2011 20.400 2012 4.425 2013 -3.675 2014 -8.000 2015 -25.225 2016 1.450 2017 16.725 2018 2.125 2019 3.025 2020 -3.325 2021 17.125 2022 -15.583 2023 15.999 2024 2.709 2025 1.896 2026 1.758 2027 1.864 2028 2.022 2029 2.254