Clarifying Misunderstanding of Life Expectancy and COVID-19




Basically, there are two life expectancy measures—
period life expectancy and cohort life expectancy.
Period life expectancy generally is based on the
assumption that current rates of death continue
indefinitely. Cohort life expectancy is more heavily
influenced by long-term expectations. Period life
expectancies can vary dramatically from one year to the
next when there is a short-term increase in mortality.


Period life expectancy can be a
useful metric for year-over-year
comparisons in normal times but
tends to exaggerate the effect of
nonrecurring events. Cohort life
expectancy is likely what most people
envision when thinking about the
concept of life expectancy because
cohort life expectancy is an estimate
of the actual number of years
that a typical individual might be
expected to live based on reasonable
expectations for future conditions.
For this reason, cohort life expectancy
is the measure used by the Actuaries
Longevity Illustrator that can help
individuals estimate how long they
might live.

Publication Date: Feb 2022

Publication Site: American Academy of Actuaries