If actual unemployment affects the non-accelerating inflation rate of unemployment (NAIRU) through a hysteresis effect, the disinflation involved in reducing a country's inflation rate to that of its future partners in a monetary union could produce a long term cost to monetary union in the form...

The trade-off between the variability of inflation and that of output is estimated for the UK, using several different approaches to obtain the output gap, and then for a range of other countries; in all cases the trade-off retains the 'sharp turning point' found for the UK and US by other authors.