Year Percent change (Units) 2000 2.515 2001 34.253 2002 -4.464 2003 3.579 2004 20.808 2005 10.037 2006 15.088 2007 30.748 2008 11.890 2009 -14.220 2010 32.340 2011 27.232 2012 24.828 2013 16.305 2014 -6.930 2015 0.686 2016 -8.246 2017 12.553 2018 6.392 2019 -20.401 2020 -17.492 2021 13.693 2022 21.315 2023 12.674 2024 -1.073 2025 5.327 2026 6.851 2027 6.933 2028 10.675 2029 9.284