A series for the GDP deflator in index form is produced by the Treasury from data provided by the Office for National Statistics (ONS) and the Office for Budget Responsibility (OBR). The GDP deflator set is updated after every ONS Quarterly National Accounts release (at the end of each quarter) and whenever the OBR updates its GDP deflator forecasts (usually twice a year).
GDP forecasts were produced at Budget 2014 and therefore data from 2014-15 onwards hasn’t been revised as a result of the methodology described above.
Outturn data are the latest Quarterly National Accounts figures from the ONS, 30 September 2014 and their subsequent corrected release of 6 October 2014. GDP deflators from 1955-56 to 2013-14 have been taken directly from fiscal period ONS series L8GG. GDP deflators from 1955 to 2013 have been taken from calendar period ONS series MNF2.
Forecasts are from the OBR as at the 19 March 2014 Budget.
The next GDP deflator update will be shortly after the Chancellor’s Autumn Statement due out on 3 December 2014.