Year	constant 2015 US$
1991	4055.0615405016947
1992	4075.534343495136
1993	4122.351816766971
1994	4355.214195610103
1995	4197.438044298733
1996	4494.691066112044
1997	4280.97441825433
1998	4703.57317821212
1999	4564.531405873792
2000	4671.325461383561
2001	4901.863784225905
2002	5297.536969086486
2003	5214.256797166245
2004	5084.067598467928
2005	5388.899994661958
2006	5719.301437505533
2007	5409.295895421627
2008	5213.554650713432
2009	5745.0591162214905
2010	6065.932748443231
2011	6497.989674852838
2012	6774.016826758367
2013	7137.064983696172
2014	7223.133991900732
2015	7441.647340445494
2016	7511.964861134328
2017	7692.825916279377
2018	8214.760810825637
2019	8842.15993541357
2020	9544.818585139532
2021	9551.901938496361
2022	9399.729304282499