摘要：This paper investigates the reasons for the levelling off of the mortality estimates at the oldest age groups and the possibility of estimating the level of the mortality rates at these ages.The research applies the method of extinct generations to estimate indirectly the population numbers at the oldest-old age groups (75 to 100+) using data on reported deaths alone, and hence, the mortality rates. After observing that the estimated mortality rates are levelling off with age at the advanced ages (age 90 to 100+) due to age exaggeration in both the deaths and the population, the Gompertz curve was fitted to the estimated mortality rates at age groups 75, 80 and 85. Our estimates are generally lower but close to the estimates derived by Dorrington et al., (2004) and the estimates from the United Nations Population Division (UNPD) and the US Census Bureau (USCB) population projections.
关键词：Old age mortality; extinct generations; age exaggeration; completeness; South Africa
