Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
An original index is introduced for measuring the extent of the overall bilateral balance of migration among countries within a region which allows comparisons of the balance over time as well as between regions and various possible sub-regions. It is shown that having constructed the index it is also possible to establish a weighting of the contribution of each country to the overall degree of migration balance within a region. The new index is applied to three sub-groupings of the European Union (EU): (a) a mix of nine northern and southern EU15 countries; (b) seven northern EU15 countries; and, (c) four southern EU15 countries. It is shown that in each case migration in the 1990s was highly balanced and improving significantly over time. However, there was a substantial difference between the northern and southern countries with the former enjoying significantly higher overall balance in migration than the latter, although the rate of improvement in balance was much higher amongst the southern countries. Finally, whilst the UK and Portugal were persistently low contributors to the overall balance in EU migration, Germany's contribution was the highest.