The United Kingdom is a highly open economy, and has a monetary policy strategy of targeting inflation in consumer prices. In this paper, we look at the evidence from the UK on inflation behaviour, and examine the propositions from several theoretical models about inflation dynamics in an open economy, focussing in particular on the hypothesised connections between the exchange rate and consumer price inflation. Theoretical open-economy macroeconomic models 'cover the waterfront' on this issue, ranging from 'exchange rate disconnect' to a rigid link between nominal exchange rate changes and inflation. We estimate on UK data the open-economy Phillips curves implied by the alternative explanations. We argue that, of the alternatives considered, only a model where imports are modelled as an intermediate good, as in McCallum and Nelson (1999), provides a reasonable match with the data. Unlike the standard model, in which imports are treated as a final consumer good, the intermediate-goods specification provides support for a policy of CPI inflation targeting.

The focus of our analysis is on how the UK government's proposed Brexit deal is likely to affect the economy. First, we assess how trade, migration, foreign direct investment, productivity and contributions to the EU budget might change by reviewing current proposals against historical evidence. Second, we use the National Institute Global Econometric Model (NiGEM) to analyse the macroeconomic effects. Our assessment is that trade with the EU, especially in services, would be more costly after Brexit. This would be likely to have adverse effects on living standards in the UK. Our central estimate is that if the government's proposed Brexit deal is implemented, then GDP in the longer term will be around 3% lower per head than it would have been had the UK stayed in the EU. If the UK were to stay in a customs union with the EU, or if the Irish backstop position was to be invoked, there would still be a hit to GDP per capita of 2%. These estimates represent our considered view of the economic impact of the government's proposed Brexit deal, but they are themselves uncertain as there is no historical precedent of a country leaving a major trading block such as the EU.

The UK's monetary policy strategy is one of floating exchange rates and inflation forecast targeting, with the targeted measure referring to consumer prices. We consider whether it is welfare-reducing to target inflation in the CPI rather than in a narrower index and the role of the exchange rate in the transmission of monetary policy actions to CPI inflation. It is appropriate to model imports as intermediate goods rather than goods consumed directly by households. This leads to a simpler transmission mechanism of monetary policy while also offering a sustainable explanation of the weakness of the exchange rate/inflation relationship and making consumer price inflation an appropriate monetary policy target. Copyright 2006 Royal Economic Society.

The financial crisis has led to a change in the mix of capital and labour employed in the UK and a sharp decline in total factor productivity. This has meant that labour productivity has not recovered to any great degree since the financial crisis. We explore the role of overall and sectoral productivity in explaining the fall in labour productivity, but also question the extent to which productivity in the service sector may be measured with error. We outline the links between a constrained financial sector and a fall in overall productivity – in which intangible capital seems to play an important role – and illustrate how a financial sector providing intermediate services may act to amplify the business cycle impetus from a total factor productivity shock within the context of a calibrated model.

Thanks to Jagjit Chadha and Iana Liadze for helpful comments and suggestions. We also thank Nathaniel Butler-Blondel for compiling the database. Unless otherwise stated, the source of all data reported in the figures and tables is the NiGEM database and forecast baseline. The UK forecast was completed on