Year constant 2015 US$ 1995 17948.88697730321 1996 19104.86672078372 1997 21468.491773974816 1998 22448.284448862905 1999 23024.005694856012 2000 25051.160919085043 2001 26162.546619139335 2002 25581.699784895995 2003 27298.704772555546 2004 29922.600419143782 2005 32113.420483932903 2006 32854.6978895273 2007 35296.08404359753 2008 33771.21813721682 2009 31045.443506350464 2010 32408.538993835762 2011 33092.77202150653 2012 32702.550996561393 2013 32266.257659843064 2014 32587.127924669494 2015 32680.081023515864 2016 33029.40447012319 2017 34409.25167674408 2018 35267.55909064061 2019 35511.95806373835 2020 36365.20094644118 2021 38593.3848417197 2022 37379.914151282734