Computer display of population age structure.

The standard human population pyramid contains only current information; it is often inadequate when making comparisons of different countries or years. A graphic computer program superimposes current population, life table survivor ships, stable population, and past population projected up to the present. Fertility, health conditions, migration, and demographic transition stage are better revealed by this expanded graph form. A time series of the modified pyramids reveals detailed age-specific trends for a country or region. With 'minor modifications the computer program is applicable to all machines with a Fortran IV compiler.