Can you point where is that PPP in the graph? Not only it is not mentioned, but not even the year of the data: "most recent" is terribly vague, even if true.
The title says “GDP Per Capita, PPP”.
Except that Central African and continental Europe climates require vastly different expenses to stay alife. PPP is not much better than US dollars.
How vast are the differences in expenses needed to live (due to climate or otherwise)?