Year	constant 2015 US$
1991	14547.871195469359
1992	14664.16195108174
1993	14619.493447661573
1994	14216.713741068257
1995	13717.416228370954
1996	13652.064869469383
1997	13582.822276677965
1998	13973.465161716891
1999	13557.530910238042
2000	12721.11228912126
2001	15303.757912042915
2002	15640.42155978517
2003	15440.56698274366
2004	16705.773701353606
2005	17109.779460841786
2006	17481.82698322689
2007	18127.286791325165
2008	18528.096363754445
2009	18286.40591990846
2010	19306.681948087957
2011	20339.47969120417
2012	20831.447437391296
2013	21295.44436396641
2014	21766.18712463058
2015	21880.585984507477
2016	21916.882183229405
2017	22537.334433809658
2018	22074.988258945134
2019	22652.179863214424
2020	21918.712580007934
2021	21997.486133544924
2022	22809.119954869162