The study is based on face-to-face interviews at 30,000 British households between 2006 and 2008, making it one of the ONS’s largest surveys. A second wave of the longitudinal study is due to be completed in summer 2010 and further waves are planned.

The ONS says the survey aims to address gaps in data about the economic wellbeing of households by collecting information on assets, savings, debt, how wealth is distributed and factors that affect financial planning. It measures household wealth in terms of property, financial, physical and private pension wealth.

Household wealth totalled approximately £9 trillion in 2006-08, according to the survey, with the poorest 50% of households holding 9% of the wealth and the richest 20% holding 62%. Median household net wealth was £204,500, with the regional median varying from a high of £287,900 in the south-east of England to a low of £150,600 in Scotland.