Year 2017 PPP (% of population) 1989 53.5 1992 49 1994 47.6 1996 60.4 1998 56.7 2000 49.9 2002 47 2004 44.2 2005 42.9 2006 39.7 2008 40.2 2010 40.2 2012 37.3 2014 40.3 2016 31.4 2018 28.8 2020 30.3 2022 21.8