Dear Sir,

We read your article “Repairing the retail prices index could save Britain billions” (FT website 20/7/17) with interest.

The position of the ONS is clear: RPI is not a good measure of inflation and we discourage its use. However, the ONS does not have the authority to stop the use of the RPI or to tell particular users which index they should use in any given circumstance.

Legislation requires us to continue to produce the RPI and we have looked hard at whether we should change the way it is calculated to remove some of its shortcomings. We concluded that changing it could have negatively affected people and organisations already using it in contracts in its current form. We view RPI as a legacy measure and instead have focused our efforts on developing better measures of consumer price inflation.

Yours faithfully,

Jonathan Athow
Deputy National Statistician for Economic Statistics