Year	2017 PPP (% of population)
1990	31.6
1991	34.2
1992	38.5
1993	44.2
1994	48.2
1995	42.8
1996	46.6
1997	44.2
1998	44.7
1999	52.4
2000	48.7
2001	45.6
2002	42.6
2003	41
2004	36.1
2005	32.6
2006	28.9
2007	25
2008	20.6
2009	20.5
2010	19.1
2011	17.4
2012	16.4
2013	14.8
2014	14.3
2015	14.5
2016	13.8
2017	12.5
2018	11.4
2019	10.8
2020	10.3
2021	8.9
2022	8.6