The number of super-wealthy individuals in the U.S. increased by 16% as of mid-year 2010 over the same period in 2009, a study by a marketing research firm finds.

Phoenix Marketing International, Rhinebeck, N.Y., found the number of ultra high net worth (UHNW) households increased after two years of declines. Its double-digit rise compares to a rise of only 4% in the overall number of affluent households since midyear 2009.

Phoenix defines UHNW households as those with $5 million or more in liquid assets. It defines affluent households as those with $250,000 or more in liquid wealth, or $150,000 or more in annual income.

As the Standard & Poor’s (S&P) 500 index shrank considerably through mid-year 2009, the number of UHNW households followed a similar pattern, Phoenix notes. Then, as the S&P 500 climbed by double digits from late June 2009 to the same period in 2010, the number of UHNW households followed suit.

In contrast, the broad affluent market in the U.S. has managed to register small gains in numbers over the past three years, the Phoenix data show.

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