| Abstract: | This brief examines the historical relationship between exchange rates and relative inflation rates for a group of major industrial countries. It establishes the concept of the ‘real exchange rate’ and the ‘productivity-adjusted real exchange rate’ (PARE) as essential in understanding these relationships and projecting them into the future. It puts the discussion into the context of company decision making, as one important factor in the rate of return likely to accrue from different methods of supplying an overseas market. Differences in productivity between countries explain the divergences in prices of ‘non-traded goods’. To give a simple example, a haircut costs much more in New York than in Madrid since high US wages reflect high productivity which does not apply in many parts of the service sector. These differences rule out the acceptance of the over simple ‘purchasing power parity’ approach which assumes that exchange rates will settle at a point where all prices (in terms of a common currency) are the same everywhere, or move together. Even after account has been taken of differences in productivity growth, productivity-adjusted real exchange rates (PARE) - though reasonably stable - can still show some deviations, or ‘blips’. The ‘blip’ may occur because of rapid changes in the actual exchange rate or in domestic prices, in which case it is likely to prove temporary and the PARE rate will tend to adjust back to its normal level. But it may come from major structural changes, in which case PARE will be altered permanently within definable limits. A way of recognising the different categories of ‘blip’ is suggested in the brief. The PARE framework is then used to provide a guide to UK businesses who are concerned to calculate the future sterling value of foreign currency sales or, more generally, to estimate their competitiveness in supplying specific export markets. (The method used would apply equally well to other countries.) This is done by showing step-by-step the forecasting procedure to compute sterling's effective exchange rate to 1981 on assumptions concerning respective rates of inflation, monetary policy and the impact of North Sea oil. The computation shows that a sustained period of exchange rate stability is possible for the UK, even if UK inflation rates remain significantly above the world level for the next two years. |
