French economist and academic Thomas Piketty, poses in his book-lined office at the French School for Advanced Studies in the Social Sciences (EHESS), in Paris May 12, 2014. The 43-year-old Piketty's book "Capital in the Twenty-First Century" has attracted praise and invective alike on its way to the top of the books best-seller list. Picture taken May 12, 2014.

New York - French economist Thomas Piketty said that if given the opportunity to revise his best-selling book, he would provide data showing a wider gap in wealth inequality than he previously thought.

Referring to a study titled “The Distribution of US Wealth, Capital Income and Returns since 1913,” Piketty said in an interview on Bloomberg Television that “if anything, what they find is an even bigger rise in wealth concentration than what I report in my book.”

The paper’s authors are economists Emmanuel Saez and Gabriel Zucman.

Piketty’s book, “Capital in the Twenty-First Century,” came under fire in a May 23 Financial Times article alleging suspect statistics and incorrect calculations.

Two of the book’s “central findings -- that wealth inequality has begun to rise over the past 30 years and that the US obviously has a more unequal distribution of wealth than Europe -- no longer seem to hold,” FT economics editor Chris Giles said in the article.

Piketty last week posted a 4,400-word defense on his personal website, saying “the FT suggests that I made mistakes and errors in my computations, which is simply wrong.”

The newspaper’s allegations weren’t discussed in today’s Bloomberg interview.

“Capital in the Twenty-First Century” has been hailed by Nobel-prize winning economist Paul Krugman as “the most important economics book of the year -- and maybe of the decade.”

Piketty has given presentations on his findings to the White House Council of Economic Advisers, the International Monetary Fund and the United Nations.


Widening Disparities


The 43-year-old professor at the Paris School of Economics examined centuries of data on countries including the US, Sweden, France and the UK to show that returns on capital in excess of economic growth lead to widening disparities in wealth.

Giles wrote that figures underpinning Piketty’s 696-page book contained unexplained statistical modifications, “cherry picking” of sources and transcription errors.

He said the mistakes undermine Piketty’s conclusion that wealth inequality in Europe and the US is moving back toward levels last seen before World War I.

One “serious discrepancy” Giles said he found was in Piketty’s data on the UK.

While Piketty cited a figure showing the top 10 percent of its population held 71 percent of national wealth, a survey by the country’s Office for National Statistics put the figure at 44 percent.

In his web posting, Piketty disputes that the book contains transcription errors and disagrees with the adjustments to the data proposed by Giles, most of which he calls “relatively minor.”


‘Quite Debatable’


“The FT corrections that are somewhat more important are based upon methodological choices that are quite debatable,” Piketty said.

In the Bloomberg interview, Piketty said he plans to shift his focus to inequality in emerging countries, including China, India and nations in Africa and Latin America.

In China, officials have addressed issues of rising inequality “mostly on a case-by-case basis,” he said.

“When someone gets really too rich, they expropriate him,” Piketty said.

“But they are starting to realise that this is not the right way to solve and to regulate the dynamics of capital accumulation, so they are talking about introducing some form of property wealth tax.” - Bloomberg News