Almost one in five new mortgages written in 2007 was either dubbed 'sub-prime' by the bank that loaned the funds or was made to a home buyer who offered no proof of income, according to an industry trade association. Financial Times (Sat)

The Intermediary Mortgages Lenders Association – mortgage brokers that sell almost all the sub-prime and self-certified loans in the UK – said the first category accounted for 8% of loans and the latter a further 10%.

Those two markets accounted for £20bn and £30bn in loans in 2005, and are presumed to have since risen further in value.

The IMLA disclosed the data as it warned against reading too much gloom into the housing picture, however – a view bolstered by surveys showing the average household owns far more equity in bricks and mortar than debt used to buy it.