Year	2017 PPP (% of population)
1981	67
1982	66.4
1983	72.1
1984	72.2
1985	68
1986	49.5
1987	59.2
1988	61.4
1989	58.3
1990	63.7
1992	65.4
1993	64.3
1995	52.6
1996	52.6
1997	53
1998	52
1999	53.8
2001	48
2002	47.3
2003	48.7
2004	47.3
2005	45
2006	41.4
2007	39
2008	35.8
2009	33.8
2011	29.9
2012	28.2
2013	25.7
2014	24.3
2015	25.3
2016	27
2017	27.1
2018	26.7
2019	26.2
2020	18.7
2021	28.4
2022	23.5