Year Percent change (Units) 2001 2.758 2002 4.431 2003 -28.974 2004 3.971 2005 5.856 2006 8.480 2007 13.103 2008 6.105 2009 5.192 2010 6.351 2011 7.700 2012 8.420 2013 8.836 2014 0.695 2015 0.007 2016 -1.630 2017 2.469 2018 1.242 2019 -2.516 2020 -2.967 2021 5.011 2022 4.811 2023 4.583 2024 5.277 2025 6.248 2026 6.234 2027 6.278 2028 7.133 2029 6.151