Year Percent change (Units) 2001 -10.866 2002 -13.415 2003 6.998 2004 6.605 2005 6.173 2006 -4.672 2007 13.427 2008 18.530 2009 -2.773 2010 -6.110 2011 -22.406 2012 9.718 2013 -4.047 2014 14.125 2015 5.920 2016 -1.950 2017 -12.212 2018 56.368 2019 -1.328 2020 -25.465 2021 -4.834 2022 7.507 2023 31.038 2024 -9.043 2025 8.258 2026 -0.452 2027 0.512 2028 0.818 2029 1.571