In December 2018, the Office for National Statistics (ONS) published an extended Consumer Prices Index including owner occupiers’ housing costs (CPIH) historical series. Previously, the series had only been available back to 2005. These new historical estimates took the series back further, to 1988. The extended series is an official statistic rather than a National Statistic, reflecting the historical uncertainty around the backcasts. However, there is a user need for a longer series still, with the ONS currently planning to produce indicative estimates back to 1947, owing to user demand.

In the course of producing the CPIH series for 1988 to 2004, the ONS identified an error in the modelled Consumer Prices Index (CPI) historical series. This only affected modelled estimates and did not constitute part of the CPI National Statistic series. The error was corrected when the CPIH historical series was published. For more information, please see the accompanying article.

The ONS previously published indicative modelled estimates for the CPI between 1947 and 1987. These estimates are for analytical purposes only and are not intended for official uses. The models used were based on the subsequently revised CPI modelled data for 1988 to 1996. The ONS will therefore produce new indicative estimates for the CPI between 1947 and 1987 alongside the planned CPIH estimates, based on the corrected CPI data. This will give users a consistent set of modelled indices. These new estimates will be published by the end of 2020.