Year	constant 2015 US$
2012	4039.8990967208056
2013	4049.8157725505866
2014	4079.903524222291
2015	4160.478069483199
2016	4430.496580268436
2017	4748.923887502405
2018	4861.375162332257
2019	5012.567062450271
2020	5022.810326554961
2021	4761.140884634541