And while the popular image of a billionaire is a brash young playboy, it looks as though amassing your wealth is a long-term task: In the wealthiest 10 percent of households in the U.K., who own 44 percent of total household wealth, 22 percent of them were 55-64 years old.
The report found individuals in this age group are still in the "wealth accumulation phase" and income, such as earnings from employment, enable opportunities to increase total wealth.
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Individuals aged between 25-34 years old were the least likely to live in households at the top total wealth band, with just 3 percent of this age group fitting into this category.
Research conducted by Oxfam in March this year showed five of the richest families in the U.K. own more wealth than the poorest 20 percent of the country, a statistic the charity described as "deeply worrying".
Sports Direct boss Michael Ashley and real estate investor Gerald Grosvenor are among five billionaires, who are collectively worth £28.2 billion ($46.9 billion), more than the £28.1 billion wealth of the bottom 12.6 million people in Britain, Oxfam revealed, citing figures from Forbes magazine.
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"It's deeply worrying that these extreme levels of wealth inequality exist in Britain today, where just a handful of people have more money than millions struggling to survive on the breadline," Ben Phillips, Oxfam's director of campaigns and policy, said at the time of the report.
Total wealth, including pension savings of all private households in the U.K. was £9.5 trillion in 2012, up from £9 trillion in 2010 and £8.4 trillion in 2006, the ONS said.