Year	2017 PPP (% of population)
1990	3.8
1991	4.3
1992	5.6
1993	6.4
1994	8
1995	8
1996	8.2
1997	7.7
1998	7.8
1999	10
2000	9.2
2001	8.3
2002	7.4
2003	7.3
2004	5.5
2005	4.7
2006	3.3
2007	2.2
2008	1.4
2009	1.2
2010	1.2
2011	0.9
2012	0.9
2013	0.7
2014	1
2015	0.8
2016	0.7
2017	0.7
2018	0.4
2019	0.5
2020	0.5
2021	0.5
2022	0.5