What will be the effect on vehicle manufacturing in the UK of the government's decision not to join the European single currency in the first wave - if at all?
The BMW-Rover group has the most to lose from the strength of sterling and Nissan is not far behind. Honda and Toyota also stand to lose. Ford and General Motors, both of which are net importers of vehicles, are roughly in balance in terms of value.
The largest gainers from a strong pound are, not surprisingly, Volkswagen, Renault and PSA.
However, Japanese manufacturers export a higher proportion of their output than any other UK-based producers. Ford and GM have been substantial exporters, but are equally substantial importers.
Companies planning to export from the UK to the Euro-zone face two problems - the absolute levels of the exchange rate and its unpredictability.
In the case of single-sourced models, manufacturers currently seek to insulate the retail prices from short-term currency fluctuations for as long as possible.
Hedging provides some protection, though most hedging contracts taken out by sterling exporters at 1996 exchange rates have now expired. Next they will take the hit on their margins. Only as a last resort will they have to raise prices.
How many sales will be lost as a result of such price rises?
It is very hard to disentangle a price effect from many other factors which determine a model's market share. Typically the cross-price elasticity of demand is estimated in the range of three: if you raise your prices 1 percent and all your competitors keep their prices stable, you will lose 3 percent of your sales.
Double-sourced models currently account for 40 percent of UK production but by 2003 this share will decline substantially.
Double-sourcing of models can provide some protection against currency volatility - far from being threatened by sterling's current strength, the rational could be seen as being reinforced.
However, when substantial volumes of UK production are exported to the Euro zone, in the case of the Vectra, for example, the case for relocating that share of output is at least as strong.
Where the output is sold outside Europe, as for example a large chunk of Jaguar's production will be, the link to the Euro will be less relevant.
But currency risk and exchange rate expectations are not the only consideration.
For example, those planning to relocate to France or Italy will need to consider the commitment to the 35-hour week in those countries. Proximity to trusted component suppliers is a prime consideration for any producer.
Many of the decisions that will boost UK production over the next five years were taken at the time that sterling was undervalued and cannot quickly be reversed.
If we extend our horizon by a further five years we would see the strong negative effect of the current period. The longer it goes on, the worse the long-term outlook.