Privately-owned Grosvenor Group has swung to a pre-tax loss of £594 mln (EUR 673 mln) in 2008 from a profit of £524 mln in 2007 mostly as a result of 'the impact on Grosvenor's portfolio of the decline in asset values in many of the markets in which it operates.' The company, which is owned by Gerald Grosvenor, Britain's third richest man, also said around £537mln has been wiped off the value of its investment properties. Net asset value was down 7.4%, from £3.1 bn to £2.8 bn.