Year Percent change 2001 1.531 2002 5.051 2003 2.914 2004 2.369 2005 3.221 2006 4.19 2007 2.285 2008 10.443 2009 -0.283 2010 -1.853 2011 0.501 2012 1.417 2013 2.008 2014 1.073 2015 3.144 2016 3.511 2017 4.12 2018 4.169 2019 3.681 2020 3.459 2021 3.377 2022 3.1 2023 2.881 2024 2.393