Year	2011 PPP (%)
1979	17
1989	30.3
1991	27.8
1995	22.2
1997	20.9
1998	21.1
1999	19.2
2000	17.9
2001	21.3
2002	17.9
2003	17.3
2004	16.3
2005	15.8
2006	16.2
2007	13.7
2008	9.8
2009	8.6
2010	9
2011	7.4
2012	8
2013	7
2014	7.1
2015	5.9
2016	5.8
2017	5.6