A Comparison of Six Methods for Decomposition of Changes in Expectation of Life at Birth and Differentials in Life Expectancy at Birth

Krishna Murthy Ponnapalli, Addis Ababa University

A Comparison of Six Methods for Decomposition of Changes in Expectation of Life at Birth and Differentials in Life Expectancy at Birth Krishna Murthy Ponnapalli Addis Ababa University E-mail: pkmurthy2001@yahoo.com Several methods were proposed to decompose the difference between two life expectancies at birth into the contribution by different age groups (See: Chandra Sekar, 1949; Lopez and Ruzicka, 1977; Pollard, 1982; Arriaga, 1984; and United Nations, 1982 and 1985).In this study an attempt is made to compare six of the different decomposition methods. The methodologies suggested by Arriaga(1984), Lopez and Ruzicka(1977) and Pollard(1982)have been extended. It is shown that all the three methods after the extension will be seen to produce the same results as that of Chandra Sekar(1949). Finally it is suggested to use that methodology where the percent contribution of total of the interaction terms to the difference in the life expectancy at birth is very negligible.