Year Percent change (Units) 1994 11.409 1995 2.361 1996 8.333 1997 17.876 1998 24.772 1999 0.183 2000 9.999 2001 -2.241 2002 3.701 2003 -19.218 2004 -8.008 2005 15.238 2006 15.648 2007 7.885 2008 4.729 2009 -10.867 2010 34.691 2011 -0.676 2012 2.001 2013 -4.510 2014 5.425 2015 19.452 2016 8.749 2017 -3.816 2018 4.255 2019 4.100 2020 -9.347 2021 17.635 2022 14.876 2023 -4.262 2024 3.624 2025 2.913 2026 2.609 2027 2.966 2028 3.909 2029 4.708