One in ten UK companies anticipate a fall in assets of more than 20% with the introduction of FRS 17, according to William M Mercer, the global consultancy firm.

The new UK accounting standard, which was introduced in November 2000 but will be phased in until June 2003, shows a mark-to-market assessment of pension schemes' financial positions, rather than their position over time as under the current standard, SSAP 24.