Our latest estimate suggests that the growth rate in the three months ending in January is 0.5% after 0.6% in the three months to December. This is a welcome moderation from a growth rate that has been persistently on or above trend for over two years. It is the first time that growth has been clearly below trend since July 2005 and does allow the Bank of England to reduce interest rates cautiously. Our track record in producing early estimates of GDP suggests that our projection for the most recent three-month period has a standard error of 0.14% point when compared to the first estimate produced by the Office for National Statistics. This comparison can be made only for complete calendar quarters. Outside calendar quarters the figures are less reliable than this. A paper describing the methodology used to produce the data was published in the February 2005 volume of the Economic Journal. From April until October 2006 our estimates were computed using the Index of Services published by ONS. However this monthly series shows considerable volatility which has caused us some problems in estimating GDP. From our November 2006 press release we have therefore reverted to using a model of private services output based on indicator variables. This means that, while all our figures for calendar quarters are fully coherent with ONS data, our estimates of monthly private service output are not. The series can be thought of as indicating the underlying value of the ONS series. For more information please telephone Martin Weale on 020 7654 1945.