Year	2017 PPP (%)
1989	50.3
1990	52.3
1991	45.5
1992	42.1
1993	36.9
1994	38.1
1995	39.2
1996	41.7
1997	33.2
1998	36.1
1999	36.9
2001	29.8
2002	33.4
2003	37.3
2004	36.4
2005	35.2
2006	31.1
2007	27.2
2008	25.7
2009	23.1
2010	24.8
2011	25.3
2012	29.1
2013	26.5
2014	25.5
2015	25.4
2016	25
2017	24.6
2018	24.6
2019	24