Year	2017 PPP (% of population)
1981	73.7
1982	73.5
1983	73.7
1984	72.7
1985	71.6
1986	69.6
1987	69.3
1988	67.8
1989	68.7
1990	68.4
1991	67.9
1992	66.7
1993	65.2
1994	63.1
1995	61.1
1996	59.3
1997	58.8
1998	58.4
1999	57.2
2000	54.3
2001	52
2002	48.1
2003	45.2
2004	42
2005	38.6
2006	36.2
2007	33.3
2008	31.5
2009	29.5
2010	26.5
2011	23.1
2012	20.7
2013	15.9
2014	13.9
2015	11.8
2016	10.6
2017	9.6
2018	8.3
2019	7.1
2020	6.5
2021	6
2022	5.4