Резюме

A model for measurement and analysis of population ageing has been developed. The already published various methods are synthesized in a complex model for measurement and factor analysis of ageing. The novice here is the further development of factor model. In that method a hipothetical population with preserved intensities of the three processes - age-specific fertility rates of women, mortality and net migration by sex and age from a previous period – is established. At these conditions two tasks of factor analysis are solved. In the first one, ageing is divided in two parts – by the three processes' preserved intensities and by their changes in surveyed period. In the second task ageing is subdivided in three parts - by change in the number of live births and by the different intensities of mortality and net migration by age in accounted period. An analysis of the persistent population ageing in Bulgaria in 1990-2000 has been conducted.