In 2003 it was adopted by the then Labour government as the best official estimate of inflation for the Bank of England to use when setting interest rates, replacing another measure, RPIX, which excluded mortgage interest payments.

BBC: New inflation measure proposed

Before April's election Deputy Le Lievre served on the Social Security Department and said he wanted to restore the previous regime of increasing pensions by RPIX - a measure of inflation equivalent to the all-items Retail Price Index, but excluding mortgage interest payments - plus 1% each year.

BBC: Guernsey deputy wants further pensions and benefits rise