Year Percent change 1996 18.539 1997 -5.84 1998 19.977 1999 4.488 2000 8.596 2001 28.887 2002 30.189 2003 18.572 2004 -0.773 2005 15.559 2006 3.35 2007 8.197 2008 -15.322 2009 -4.671 2010 29.615 2011 5.761 2012 7.589 2013 9.539 2014 8.217 2015 16.28 2016 19.944 2017 13.766 2018 -0.902 2019 8.64 2020 4.622 2021 4.088 2022 4.206 2023 5.046 2024 4.281