(CNN) -- The world's super-rich had between $21 trillion and $32 trillion of wealth hidden in tax havens by the end of 2010, a new study says. The size of these unreported financial assets is equivalent to, or even larger than, the combined GDPs of the United States and Japan, representing up to $280 billion in lost tax revenues. The study, titled "The Price of Offshore Revisited," was released Sunday by the advocacy group Tax Justice Network. Written by James Henry, former chief economist at McKinsey & Co., the study drew data from the World Bank, the International Monetary Fund, the United Nations and central banks.
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Global super-rich had at least $21 trillion of wealth in tax havens, a new study says
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The size is equivalent to combined U.S. and Japanese economies
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The study was released Sunday by advocacy group Tax Justice Network
The @placeholder says the estimated offshore fortune is conservative, adding it excludes non-financial assets such as real estate, yachts and artworks.