Thanks to substantial improvements in child and adult survival through most parts of the world
in the last decades, old-age mortality accounts now for large fractions of death. Yet for many developing
countries, old-age mortality is often only inferred by model life tables using mortality data at young ages,
or sometimes at young and adult ages; and reliable estimates of old-age mortality using data collected
from old-age population can hardly be found. Based on the fact that migration is rare and death risk is
high at old ages, this paper proposes a new indirect method, namely the Census method, to estimate old-
age mortality, using census data on old-age population. This new indirect Census method aims to
eliminate the effects of age-reporting errors, and is composed of three models. The first model is the
variable-r method that converts the census populations into the person-years of the underlying
stationary population. The second is an adjustment model, which uses a common relationship between
the survival ratios that is found in model life tables to eliminate the effects of age-reporting errors in
censuses. And the third is the extended Gompertz model, which estimates the number of survivors at
exact ages of the underlying stationary population based on the most commonly observed mortality
pattern. Examples are provided using census data from developing countries in Africa and Asia.