Year	constant 2015 US$
1991	28879.061455346626
1992	29064.28521851255
1993	28722.175332267245
1994	28611.567279458926
1995	28722.646083930802
1996	29244.511803173977
1997	26116.69702073243
1998	26700.97106709529
1999	27531.431625317426
2000	27386.953041271736
2001	27401.2058815768
2002	27430.501278610736
2003	27017.857559512435
2004	27240.664275766238
2005	27342.109836134758
2006	29691.67897448999
2007	30362.71787346146
2008	29393.133645405036
2009	28902.935159554538
2010	28713.537424882994
2011	28372.64939963775
2012	28455.17116840126
2013	28025.81370329076
2014	28200.83737613319
2015	27890.98943004263
2016	27329.45032310632
2017	26845.71715813273
2018	27359.09012766778
2019	27672.82065754274
2020	24355.494813252484
2021	25913.89883434117
2022	27392.907132476084