America's millionaires are bouncing back.

The number of U.S. households with a net worth of $1 million or more, not including a primary residence, increased 16%, to 7.8 million last year, according to a report released Tuesday by Spectrem Group, a Chicago research company. The increase follows a 27% decline in millionaires from 2007 to 2008.

The number of ultrawealthy households, which have a net worth of $5 million or more, rose 17%, to 980,000 last year.

"The nation's millionaires — together with its ultra-high-net-worth households — are bouncing back from the recession," said George H. Walper Jr., Spectrem's president. "While still well short of its all-time high of 9.2 million in 2007, this year's growth in the millionaire population is nevertheless welcome news for an economy still working to recover."

In addition, affluent households, which have a net worth of more than $500,000, increased 12%, to 12.7 million last year.

Spectrem surveyed more than 3,000 affluent households throughout 2009. This included an online survey of 1,498 households with a net worth of $100,000 to $1 million in July, and 1,089 households with a net worth of $1 million to $5 million and 523 households with a net worth of $5 million to $25 million in November.

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