Year	2017 PPP (%)
1981	36.8
1982	36.8
1983	42.4
1984	42
1985	38.2
1986	23.8
1987	31.7
1988	33.8
1989	31.7
1990	35.7
1992	35.6
1993	34.6
1995	26.3
1996	26.8
1997	27
1998	25.7
1999	26.7
2001	23.6
2002	22.8
2003	23.6
2004	22.3
2005	20.8
2006	18.4
2007	17.3
2008	15.3
2009	14.4
2011	12.4
2012	11.2
2013	10
2014	9.2
2015	9.9
2016	11
2017	11.2
2018	11.1
2019	11
2020	6.3
2021	11.7
2022	9