Structural changes in Sri Lankan population

Abstract

Sri Lanka is now experiencing significant changes in population structure. The most salient features are low population growth rate and increase of aged population. Given the fact population changes are the driving force behind the development planning, it is of paramount importance to statistically analyze there changes and make necessary prediction.

Based on the data obtained from the Department of Census and Statistics and the Department of Registrar General, the structural change, with special emphasis in aged population was first analyzed and then modeled using Chi-square test, MANOVA test, Chow test and Regression modeling.

The overall evaluation finds that, the elderly population has increased and female elderly population longevity is higher than male elderly population longevity after 1980 due to health reason. Comparing the overall results, log-lin regression model is the best model for forecasting total, aged, aged male, aged female, child dependency and dependency population in Sri Lanka.

In 2011, the Sri Lankan’s total population and aged population are expected to be 20,873,000 and 2,734,360 respectively, projected by Siddhisena and Ratnayake(1998). From this study the projected the total population and aged population based on the log-lin regression model is expected to 92,121,380 and 1,871,320 respectively.

The population growth rate has increased from 1967-1979 and it has decreased from 1980-2004 due to migration caused by ethnic crisis and the open economy introduced by the Sri Lankan government. Within these two periods there is a population structural change in the total population while there is no population structural change in aged male and aged female population in Sri Lanka.