[Waves in demographic time series]

"This article examines whether births, deaths and marriages since 1840, and immigrants and emigrants since 1900 in the Netherlands exhibit regular cycles. For this purpose spectral analysis is applied to the series of annual numbers per 1,000 inhabitants after removal of a long-term trend. The trend is estimated by fitting a cubic spline function." It is shown that "both births and marriages show a cycle of more than 20 years. Deaths do not exhibit a clear-cut cyclical pattern. Both immigration and emigration show a long cycle of about 20 years and a shorter one of 5 to 8 years." Different cycles are evident if the examination is limited to post-World War II data. "It should be emphasized, however, that all these cycles explain only a limited fraction of the total variation in the series." (SUMMARY IN ENG)