A Technique for Estimating Life Expectancies at Older Ages in Destabilized Populations with Application to Some Developed and Less Developed Countries

Subrata Lahiri, International Institute for Population Sciences (IIPS)

This paper presents a technique for estimating the ratios e(x+10)/e(x) over ages from two enumerations in a closed population following Generalized Population Model, which, in turn, are used to estimate life expectancies at older ages. The proposed technique makes use of an invariant property of the age-pattern of the ratio e(x+10)/e(x) over various mortality levels [e(0)] within a specified model mortality pattern. To test the validity of the procedure, the present technique has been applied to different quality of age-data starting with the age-data of Japan (1965-70) having reasonably good age-reporting followed by those of Korea (1990-95) and China (1982-90) with moderate error in age-reporting, and finally with those of India (1981-91) that are heavily distorted due to age-misreporting. The estimated e(x) values at older ages, so obtained, are sufficiently close to those obtained through life tables based on age-specific death rates for the above countries during the afore-mentioned periods.