The process of rectangularization of the survival curve in selected Eastern European countries

Klara Tesarkova, Charles University in Prague
Boris Burcin, Charles University, Prague
Ludek Sidlo, Charles University, Prague

The purpose of this paper is to give an overview of past and recent trends in the development of the process of rectangularization of the survival curve in selected Eastern European countries (the Czech Republic, Poland, Hungary, Russia, Bulgaria) for which data are available in Human Mortality Database. Whenever useful, we made a comparison with Sweden, a representative of developed low mortality countries. The process of rectangularization is defined as a trend toward a more rectangular shape of the survival curve thanks to an increasing number of survivors and concentration of deaths around the modal age of death in a population. That means that variability of the age at death is decreasing and deaths are “compressed” to a higher age. In this study we used almost thirty indicators, some of which are commonly applied in demographic analysis and some were developed or adjusted specifically for the analysis of the rectangularization process. The first group of measures represents indicators connected with the standard life table – life expectancy as well as median and modal age at death. All those indicators express increasingly better mortality conditions, the rising average age at death and also aging of society. The latter group (such indicators as natural length of life, interquartile range of deaths, or Keyfitz`s H) illustrates transformations of the survival curve and their links to various parameters of the length of life. In conclusion, we demonstrate that the rectangularization is a universal, long-term trend in human mortality patterns observed in all selected countries during the last few decades. On the other hand, in some countries deceleration of the rectangularization process could be seen. It is not because of worsening mortality conditions but due to an increase in the survival of the oldest-old. As a result, the survival curve has started to move rightwards.