The RBS Group Pension Fund, one of the largest schemes in the UK, all but wiped out its deficit during 2016 thanks to a bumper cash payment from its parent and an investment return of almost 30%.

The £4.2 billion cash payment, the UK's largest-ever pension contribution, accounted for a big chunk of the scheme's £13 billion gains during the year - but its programme of hedging liabilities using gilts and interest-rate swaps was also key.