Year Percent change 1991 6.127 1992 5.966 1993 4.502 1994 4.151 1995 3.555 1996 2.317 1997 1.813 1998 1.699 1999 3.168 2000 2.535 2001 2.747 2002 2.828 2003 2.079 2004 5.041 2005 6.028 2006 12.027 2007 11.253 2008 8.804 2009 0.201 2010 1.721 2011 0.156 2012 0.601 2013 1.443 2014 3.108 2015 3.596 2016 1.617 2017 1.967 2018 3.08 2019 2.135 2020 2.056 2021 2.093 2022 2.114 2023 2.086 2024 2.225