Year Percent change (Units) 2002 -1.569 2003 -1.353 2004 2.799 2005 5.610 2006 4.586 2007 7.114 2008 6.163 2009 0.757 2010 3.913 2011 6.809 2012 5.829 2013 5.717 2014 5.594 2015 3.733 2016 1.444 2017 2.041 2018 2.944 2019 2.561 2020 -0.865 2021 1.000 2022 0.766 2023 1.415 2024 1.700 2025 2.250 2026 2.400 2027 2.500 2028 2.500 2029 2.500