Year constant 2015 US$ 1991 4868.335420201039 1992 4788.847224031126 1993 4671.525669081878 1994 4611.615594563738 1995 4582.018168944733 1996 4523.6215985170065 1997 4521.089552388509 1998 4510.901200765049 1999 4498.8093185688795 2000 4399.631393701964 2001 4417.212136969845 2002 4601.354240067173 2003 4530.380153523068 2004 4984.180280972055 2005 5192.2081492403595 2006 5347.782451009706 2007 5597.782648737261 2008 6024.317709716973 2009 6267.612185371005 2010 6622.587736159995 2011 6655.016390716802 2012 6795.67790977607 2013 7090.4459348262335 2014 7262.482564941186 2015 7220.684162239264 2016 7118.756513333467 2017 7012.996969638491 2018 6958.4540734061575 2019 7011.386417069142 2020 6892.386900248154 2021 7041.488462119588 2022 7078.176464829169