Year	constant 2015 US$
1977	4186.598877328544
1978	4539.167753881232
1979	4629.848382116569
1980	4446.2763773581
1981	4640.023429520943
1982	4651.060211028243
1983	4796.632770095283
1984	5059.071568888817
1985	5390.619971215261
1986	6072.787698997643
1987	6220.171223180663
1988	6988.696578936031
1989	7518.908480509095
1990	8155.5110531640585
1991	8074.536711703213
1992	8588.597319139313
1993	8512.240679822724
1994	8535.385751350193
1995	8582.735569319653
1996	8740.572878661667
1997	8596.985731531267
1998	9055.818896666378
1999	9215.354067115504
2000	9147.937397325339
2001	8775.975997989086
2002	8746.892217768664
2003	9050.107232378397
2004	9637.358961111748
2005	9531.252774121089
2006	10055.828846695586
2007	10161.96121395315
2008	10597.975341529074
2009	10230.683265819584
2010	10189.565529442852
2011	10555.741128124675
2012	10484.634301965018
2013	10223.981151676637
2014	10330.408561169936
2015	10292.733530008829
2016	10597.882421809732
2017	10909.670249407276
2018	11178.861328829877
2019	11062.53524545579
2020	8321.253574378738
2021	9317.414118614723
2022	10988.971428072353
2023	11314.734327866032