It's the Singapore way: Very wealthy and still living with mum

Car buyers in Singapore must bid for a limited number of permits -- called Certificates of Entitlement -- that are auctioned by the government. It's tool used to control pollution and congestion and can more than double the vehicle’s market value. Consequently, an average family sedan can cost almost as much as a home in the U.S.

The country went from third world to first in two generations. Singapore took 22 years to double its GDP per capita, about half the time of other developed economies including Australia. Its GDP per capita was S$71,318 ($52,000) in 2014, among the highest in the world. The island also has among the highest proportions of millionaire households, according to Boston Consulting Group.

The majority of housing in Singapore is built by the government. More than 80 percent of the resident population lives in such accommodation, which is typically cheaper than privately developed properties. Because of these dynamics and a rule that prohibits most single Singaporeans from buying a public housing apartment while single -- unless they are at least 35 years old -- an overwhelming majority of unmarried adults live with their parents. And are big fans of Airbnb.

Singapore is among a handful of developed nations with compulsory military service for its male residents and citizens. The National Service is for a period of about two years, and typically begins at age 18, unless there are exceptional circumstances -- like training for the Olympics, for example.