Year	constant 2015 US$
2010	51879961312.94053
2011	59279118796.95116
2012	63835993022.99643
2013	61287041489.16272
2014	62147747807.20421
2015	61608365575.100044
2016	63124657711.22888
2017	60113479362.704956
2018	59900925832.15673
2019	53880823578.76893
