Dictionary of population terms

life table

Русский: таблица смертности
Français: table de mortalité

- one of the most important demographic tables, system of indicators, that quantitatively describe the age changes in some population caused by mortality. It is presented as a set of interrelated age functions.
L.t. contains the following basic indicators:
l_x - the number of survived by the age x, l₀ - a starting point, usually 100000;
q_x - death probability, the probability that someone aged exactly x will die before their (x+1)st birthday;
p_x - the probability of surviving from age x to age x+1;
d_x - the number of deaths at age x, i.e. people who die aged x;
L_x - the number of living at age x to x+1;
T_x - the number of coming person-years to live for those survived by age x;
e_x - life expectancy at age x.

At calculation of L.t. the following relations between these indicators are used:

p_x = 1-q_x; d_x = l_x - l_x+1 = l_x * q_x; L_x = ( l_x + l_x+1 ) / 2; T_x-1 = T_x + L_x-1; e_x = T_x / l_x.

The following types of life tables are distinguished:
complete life tables, where 1-year age intervals are used from 0 to 100 or 110,
abridged life tables, that use 5- or 10-year age intervals,
cohort life tables or horizontal L.t. based on mortality indicators calculated for a real cohort (generation),
vertical life tables, calculated basing on mortality indicators of imaginary cohort for example for some calendar period,
cause-of-death life tables, that take into account influence of separate causes on survival order.

Sources of data for calculation of L.t. are population statistics and estimates of age-sex structure of population. Calculation of life tables for population of Russia and its regions is performed by Federal State Statistics Service (Rosstat, the former Goskomstat). The most important aggregated indicator of mortality calculated basing on period life tables, life expectancy at birth for males and females, is publiched in The demographic yearbook of Russia. Collection of data on mortality and calculation of L.t. is performed also by national statistical services of other countries. Deatiled statistical data on population deaths are collected by The World Health Organization from national sources and it also calculates the life tables by countries of the world.
Life tables for population of Russia during the 30-year period starting with 1970 are placed in Information-analytical system.
Internet databases that contain rich set of life tables by countries of the world:
The Human Life-Table Database
The Human Mortality Database
The Kannisto-Thatcher Database on Old Age Mortality at the Max Planck Institute for Demographic Research.

The information-analytical system is developed under the support of the Russian foundation for humanitarian research,
project 04-02-12003-в "Development of information system of social-demographic data with the Internet access".

Version of page dic_lifetable.php - 1.0. Last updated 04.02.2006.