Singapore has the highest percentage of millionaire households.
According to a study reported in the Financial Times, more than 15% of Singapore households are millionaires. No other country comes close (#2 Switzerland has less than 10% millionaires.) Singapore will soon have a million millionaires, out of a population totaling a mere 5 million. I expect the number of Singaporean millionaires to rise sharply in the next few decades. Recall that Singapore only recently became a very rich country (in income terms.) Given its high saving rates, the younger generation will get to a million dollars much quicker than the older generation. I’d guess that roughly half of Singaporeans in their 50s and 60s will be millionaires by 2040. And the younger generation at that time will hope and expect to get there someday.