Livsløpstabeller

Livsløpstabeller, also known as life tables or mortality tables, are statistical tools used to describe the mortality experience of a population. They present the probability of dying at each age, as well as life expectancy at birth and at different ages. These tables are crucial for actuaries, demographers, and public health professionals for various purposes.

The construction of a life table involves collecting data on deaths and population size at different age intervals. From this raw data, several key values are derived. The probability of dying between age x and age x+1, denoted as qx, is a fundamental component. This is then used to calculate the number of survivors at each age, lx, out of an initial cohort (often 100,000 births). The number of deaths between age x and x+1 is dx.

A critical output of a life table is life expectancy at age x, denoted as ex, which represents the average number of additional years a person of age x is expected to live. Life expectancy at birth (e0) is perhaps the most commonly cited statistic, offering a general measure of population health and longevity.

Life tables are essential for insurance companies to price life insurance policies and annuities, as they estimate the duration of risk. Governments and researchers use them to analyze population trends, understand the impact of health interventions, and forecast future demographic changes. Variations exist, such as period life tables, which reflect mortality rates at a specific point in time, and cohort life tables, which track the mortality of a specific group of individuals born in the same year throughout their lives.