Year	2011 PPP (%)
1999	39.3
2001	41.3
2002	39
2003	36.8
2004	29.9
2005	24.6
2006	21.5
2007	18.3
2008	16.2
2009	20
2010	20.3
2011	19.1
2012	17.7
2013	17.1
2014	16.7
2015	14.8
2016	14.2
2017	14.4