Year	constant 2015 US$
2006	22429.439992931937
2007	22984.96522084247
2008	22675.91353833246
2009	21858.88386961853
2010	20771.03151565773
2011	18479.68235269065
2012	17804.20453190535
2013	17423.127315211368
2014	17839.645018569194
2015	18069.157347529417
2016	18060.064060933175
2017	18231.047825759026
2018	18298.15265467377
2019	18657.958912782353
2020	17082.859396798336
2021	18451.638967468913
2022	19430.73927396395