Construction of the new United Nations model life table system.

Previous systems of model life tables were based on empirical data from the now developed countries (the Coale and Demeny models) or, when patterns from less developed countries were included (the original UN set and the Lederman set), included data of poor or unknown quality. However, with the advent of new demographic techniques of data evaluation and of improved survey, census, and vital registration systems, it has become possible to construct a new model life table system based on reliable data from less developed countries and hence more applicable to demographic analysis within that milieu. The new UN model life tables are based on carefully evaluated age-sex specific mortality data found in developing countries. Analysis of these data indicated 4 major age patterns of mortality. These patterns have been labelled the Latin American pattern, the Chilean pattern, the South Asian pattern, and the Far Eastern pattern, according to the geographical region predominant in each pattern. An overall average pattern, labelled the general pattern, has also been constructed. Along with the model life tables themselves, the UN is also producing models of sex differences in life expectancy, single-year mortality, and stable populations. A manual of computer programs to facilitate use of these models is also being prepared.