The Lee-Carter approach for life expectancy analysis and mortality forecasting in Sri Lanka

A person's life expectancy is one of the statistical measures used to determine how long they will live. However, in Sri Lanka, there is a lack of long-term, data-driven mortality forecasting, which limits the ability to make informed decisions in public health, insurance, and policy planning. This study addresses this gap by applying the Lee-Carter (LC) mortality estimation method to improve life expectancy analysis and mortality forecasting. In general, a life table that details the effects of mortality is used to calculate life expectancy. As a result, mortality predictions and life table analysis are important in the insurance, actuarial science, government, and pension planning sectors. The Registrar General's Office and the Department of Census and Statistics in Sri Lanka provided the mid-year population data and deaths as historical data for this study from 1992 to 2014. The Lee-Carter (LC) mortality estimation method is used to forecast mortality using actual death rates and mid-year populations from 1992 to 2014. ax (the average age-specific log mortality rate over time), bx (the sensitivity of mortality at each age to changes in the mortality index), and kt (the overall mortality index over time) parameters are estimated using the Singular Value Decomposition (SVD) method in the Lee-Carter methodology between 1992 and 2014. kt is forecasted for the years 2015–2035 using the traditional time series approach, and no specific time series model such as ARIMA or Exponential Smoothing was used. In 2035, the probability of dying as a 55-year-old woman and man are 0.023 and 0.051, respectively, according to the research. The following is a statement of the study's results: South Asia's average life expectancy is 69.41 years, while Sri Lanka's is 74.5 years. A country's future can be improved by thoroughly investigating demographics and life expectancy, as these factors directly affect financial stability.