TL;DR: FT used some GB data that even the original agency HMRC no longer used after methodology change. For the "Wealth Inequality in Britain 1810-2010" data,

TL;DR: FT used some GB data that even the original agency HMRC no longer used after methodology change. For the "Wealth Inequality in Britain 1810-2010" data, FT 'argues that Piketty’s graphs simply “do not match” his underlying data on the UK, and that official estimates show no significant increase in the country’s concentration of wealth since the 1970s.' (From: http://www.slate.com/blogs/moneybox/2014/05/23/financial_times_on_piketty_his_data_is_wrong.html http://www.slate.com/blogs/moneybox/2014/05/23/financial_tim...) FT's Giles then used the following data to rebuke Piketty's "overestimation" of the top 1% & 10% wealth share, as noted in Giles' Excel sheet (not in the text): "Data comes from Inland Revenue tables. They are accurately transcribed. http://webarchive.nationalarchives.gov.uk/20120403124426/http://www.hmrc.gov.uk/stats/personal_wealth/13-5-table-2005.pdf" http://webarchive.nationalarchives.gov.uk/20120403124426/htt... Excel: http://interactive.ftdata.co.uk/files/docs/FTPikettyspreadsheet22May2014.xlsx http://interactive.ftdata.co.uk/files/docs/FTPikettyspreadsh... The only problem I have is that the "13-5-table-2005.pdf" is a table before HMRC made major change to the methodology and its historical tables: http://webarchive.nationalarchives.gov.uk/20120403124426/http://www.hmrc.gov.uk/stats/personal_wealth/menu.htm http://webarchive.nationalarchives.gov.uk/20120403124426/htt... HMRC concluded with "... we would no longer be able to produce the marketable wealth series used in tables 13.3 and 13.4", which the table 13.5 relied on. And those historical tables (prior 2001) never exist again in the following years. By the way, HMRC Personal Wealth data only covers partial estates: "For 2001 to 2003 this covers 35% of estates and for 2005 to 2007, 34% and for 2008-10, 31%."