THE NEW MEASURES OF THE POPULATION AGEING

The population ageing is usually measured by the proportion of the elderly people in the population HCR (i.e. persons at the age above a certain threshold z). That measure does not take account for the distribution of age among the elderly. It is sensitive only to changes in the size of the elderly population and the total population but it ignores the age distribution of the elderly also important from the point of view of an advancement in ageing. The paper presents new measures of the population ageing for which and idea has been taken from economics on poverty: - the absolute ageing gap AG defined as the difference between a average age of the elderly 'mi' and the age limit 'z'; - the relative ageing gap RAG which expresses the absolute gap in terms of mean 'mi' and takes values from the interval '0,1 in square brackets'; - the synthetic measure HRAG = HCR x RAG; - and the index P2 = HCR x (Vsquare + RAGsquare), where V is the coefficient of the age variation among the elderly. These new measures have been tested for analyses of the ageing process in 4 European countries in 1980- 1996: Austria, France, Spain, Sweden. The results of empirical analysis confirm that the fraction of the elderly named here as the head-count ratio HCR should be treated only as a partial measure of ageing. The proposed new measures of ageing reveal new features of ageing process which cannot be reflected by the traditional measure like the HCR. Therefore, it is suggested to extend analytical tools applied to analyse the population ageing by these new indicators which are easy for calculation.