Year	2017 PPP (% of population)
1981	93.7
1982	93.4
1983	92.8
1984	91.9
1985	91.2
1986	90.3
1987	88.9
1988	86.6
1989	87.9
1990	87.2
1991	86.2
1992	84.4
1993	82.4
1994	79.7
1995	76.9
1996	74.1
1997	72.9
1998	72.5
1999	70.5
2000	67.9
2001	65.1
2002	60.7
2003	57
2004	53.4
2005	49.1
2006	46.9
2007	43.1
2008	40.9
2009	37.6
2010	33.8
2011	29.6
2012	26.7
2013	20.3
2014	17.6
2015	14.7
2016	12.8
2017	11.3
2018	9.5
2019	7.8
2020	7.4
2021	6.7
2022	6.3