Year	2011 PPP (%)
1981	20.1
1986	11.4
1989	11.2
1990	9
1991	10.5
1992	8.6
1993	7.6
1994	6.1
1995	6.5
1996	7.4
1997	5.7
1998	4.5
1999	5.7
2000	5.9
2001	4.4
2002	4.1
2003	3.9
2004	3.7
2005	2.8
2006	2.9
2007	1.7
2008	2
2009	2.2
2010	1.5
2011	1.6
2012	1.5
2013	1.5
2014	1.4
2015	1.4
2016	1.3
2017	1