Year	2017 PPP (%)
1984	67.5
1985	63.6
1986	55.5
1987	55
1988	53.5
1989	55.4
1990	55
1991	54.6
1992	53.8
1993	52.7
1994	50.9
1995	49.1
1996	47.8
1997	47.6
1998	47.5
1999	46.6
2000	44.4
2001	42.7
2002	40
2003	37.8
2004	35.4
2005	32.8
2006	31.1
2007	29
2008	27.6
2009	26.1
2010	23.9
2011	21.5
2012	19.6
2013	16.1
2014	14.6
2015	13
2016	12
2017	11.2
2018	10.1
2019	9.2
2020	8.9
2021	8.1
2022	7.6