Year Percent change (Units) 2001 11.662 2002 2.694 2003 1.152 2004 -1.065 2005 -1.385 2006 0.637 2007 4.338 2008 9.343 2009 -2.419 2010 3.501 2011 7.324 2012 2.492 2013 1.762 2014 0.425 2015 -0.528 2016 0.240 2017 1.495 2018 1.098 2019 2.716 2020 0.218 2021 3.306 2022 11.674 2023 5.223 2024 3.491 2025 2.259 2026 1.873 2027 2.000 2028 2.000 2029 2.000