The UK's Office for National Statistics surprised the pensions industry this morning by deciding to leave a key inflation metric, RPI, unchanged after a three-month review - and the gilts and swaps markets shifted as widely held expectations of a change were unwound.

The ONS had suggested altering the Retail Prices Index to bring it closer into line with another measure, the Consumer Prices Index, which has consistently reported inflation figures between 0.5 and 1 percentage point a year lower.