Year	2011 PPP (%)
1990	19.6
1997	27.5
1999	32.5
2000	36.3
2001	31.3
2002	32.9
2004	24.5
2005	27.5
2006	24.3
2007	22.3
2008	18.1
2009	16
2011	12.3
2012	13
2013	11.4
2014	10.6
2015	10.7
2016	11.2
2017	10.4