Year	constant 2015 US$
2003	14470.631555831133
2004	15802.679048252592
2005	16815.67468156418
2006	17330.6045081896
2007	17605.924036618017
2008	17693.517478180893
2009	17822.689284980504
2010	17573.06782205921
2011	17646.79212941065
2012	17507.21193316605
2013	17415.524161914545
2014	17597.550938720502
2015	17686.55208276978
2016	17926.444174396962
2017	18086.37732136446
2018	18410.130218219532
2019	18435.833714466724
2020	18459.12201152774
2021	18948.84259181973