Year	2017 PPP (%)
1981	39
1986	28.2
1989	21.6
1990	20.6
1991	23.9
1992	21.3
1993	18
1994	15.2
1995	15.9
1996	17.8
1997	15.7
1998	13
1999	14.9
2000	15.1
2001	11.5
2002	11.1
2003	10.8
2004	10.8
2005	9.4
2006	9.2
2007	7
2008	6.9
2009	6.9
2010	5.3
2011	5.7
2012	5.2
2013	5.3
2014	5.1
2015	5.1
2016	4.7
2017	4.1
2018	4.8
2019	4.3
2020	7
2021	4.6
2022	4.4