The number of millionaires is on the decline in the United States, even as the number of wealthy individuals has increased worldwide, CNNMoney reported.

Millionaire households in the United States decreased by 129,000 in 2011, according to a new study from Boston Consulting Group. Globally, that figure grew by 175,000. The report defines these millionaire households as those having more than $1 million in cash, stock and other assets, excluding property, businesses and luxury goods.

Singapore has the highest proportion of millionaires in the world; 17 percent of all households in the Asian city-state have wealth exceeding $1 million. By comparison, 4.3 percent of households in the United States had wealth of more than $1 million, which ranks it seventh in the world.

The United States also lagged when it came to the proportion of “ultra-high-net-worth” households, defined by Boston Consulting Group as those with more than $100 million in wealth.

Switzerland topped the list with 11 in every 100,000 households qualifying as “ultra-high-net-worth,” followed by Singapore with 10 in every 100,000 households.

The United States didn’t make the top 15, the report said.