Year	constant 2015 US$
2004	683.567639810119
2005	647.7828741608072
2006	623.0866841812996
2007	624.5436765681017
2008	646.3734088355006
2009	666.2935155306299
2010	684.3712323688475
2011	607.1120277419582
2012	620.7405470480013
2013	618.8566952414053
2014	591.2764790153745
2015	597.0027581095163
2016	594.7129265528112
2017	606.9373815098544
2018	634.6351512678177
2019	657.852566376897
2020	646.376615412905
2021	656.300258476688
2022	678.627567788313
2023	698.3353092433854
