Shaftesbury, the owner of property across the West End of London, has seen a quarter wiped off the value of its net asset value over the past year.

The group's property portfolio fell in value by 15.6 per cent in the year to the end of September, outperforming the IPD UK benchmark fall of 22.6 per cent, although the company said the market slump had again accelerated since that date. Net asset value per share fell a quarter from 646p to 482p.