Year	2017 PPP (%)
1990	24.7
1991	25.7
1992	26.3
1993	26.9
1994	27.3
1995	26.9
1996	26.4
1997	26
1998	25.7
1999	25.3
2000	25.2
2001	24.5
2002	23.7
2003	22.8
2004	21.2
2005	20.2
2006	19.1
2007	18.2
2008	17.2
2009	16.9
2010	15.8
2011	15.1
2012	14.5
2013	14.1
2014	13.8
2015	13.9
2016	13.9
2017	13.8
2018	13.6
2019	13.6