Year Percent change 1996 23.166 1997 24.966 1998 6.14 1999 -12.351 2000 4.976 2001 17.576 2002 18.582 2003 8.856 2004 15.211 2005 16.831 2006 14.259 2007 10.809 2008 12.188 2009 -27.997 2010 18.671 2011 15.007 2012 6.645 2013 9.112 2014 3.096 2015 6.815 2016 3.818 2017 12.02 2018 4.348 2019 4.243 2020 5.428 2021 5.059 2022 5.031 2023 4.667 2024 4.671