To ask the Chancellor of the Exchequer what estimate he has made of the impact on the measurement of inflation of moving from the RPIX method to the Harmonised Index of Consumer Prices method in (a) each of the last five years and (b) the next three years; and if he will make a statement. [113577]

RPIX and HICP inflation data are published monthly by the ONS in their First Release on consumer price indices. Projections for RPIX and HICP inflation to 2005 were presented in Box B7 of the 2003 Budget report.