Earlier quoted context omitted.
List of IMF ranked countries by GDP: https://en.wikipedia.org/wiki/List_of_IMF_ranked_countries_b... Has different numbers. Though, several other places don't seem to agree with those numbers. So, they may be off.
Sort the GDP (PPP) per capita column in descending order. It's Qatar, Luxembourg, Singapore, Brunei, Kuwait, Norway, United Arab Emirates, San Marino, Switzerland, United States.
^2 PPP is calculated by dividing GDP (nominal) by GDP (PPP), expressed as a percentage.