The existence of migrant cycles in the Portuguese emigration towards France

Abstract

In the analysis of any temporal statiscal series one may distinguish different and overlapped waving kinds of behaviour. Thus it may happen that a century-old behaviour (tendency) is overlapped by a cyclical behaviour and even a variable aleatory behaviour (fluctuations). In this article one presents an example of cyclical behaviour in Portuguese emigration, represented by the annual totals of Portuguese permanent workers arrived in France in the different years between 1950 and 1973 inclusive. The study of this chronological series of numeric values, after making different statistical operations and serial graphic representations, reveals a variation of a century-old type (tendency) very well characterized and, overlapping this, a clear cyclical variation. The cycles identified are four: from 1950 till 1956, from 1956 till 1962, from 1962 till 1968, and from 1968 till 1974. These cycles, therefore, are not equal all of them: the cyclicity of the phenomenum is not perfect. Nevertheless one may establish that the periodicity of the cycles oscillates between six and eight years.