The Royal Bank of Scotland has announced a 74% drop in third-quarter revenues at its trading division, NatWest Markets, in results one investment banking analyst described as “deplorable”.

The majority state-owned UK bank reported revenues of £150m at the unit — a much-shrunken remnant of the large investment banking division RBS established in the years running up to the 2008 financial crash. That was a steep decline from £569m in the third quarter of 2018.