Year	constant 2015 US$
2006	623.5222988952587
2007	647.3321331957379
2008	612.512131126136
2009	596.68363691335
2010	570.0047018064269
2011	578.3901250728784
2012	609.5016914885889
2013	650.0214277831554
2014	622.0989004678347
2015	648.8900527714187
2016	676.032748739052
2017	665.4347917857301
2018	671.556957651105
2019	718.6129998724257
2020	731.8619595565219
2021	738.9581234033437
2022	764.0697730577898
2023	721.3409363581205