Year Percent change (Units) 2003 0.375 2004 -3.736 2005 0.776 2006 1.027 2007 10.546 2008 0.460 2009 0.114 2010 6.514 2011 3.541 2012 3.731 2013 0.500 2014 -0.398 2015 -0.181 2016 1.292 2017 0.486 2018 2.913 2019 1.247 2020 0.056 2021 6.666 2022 12.214 2023 2.513 2024 3.448 2025 1.541 2026 2.000 2027 2.000 2028 2.000 2029 2.000