Life Table is a table of data on survivorship and fecundity of individuals within a population. It is use to examine the mortality changes in the Social Security population over time. Life table is also a concise way of showing the probabilities of a member of a particular population living to or dying at a particular age. It also used extensively in biology and epidemiology. It can be constructed using projections of future mortality rates, but more often they are a snapshot of age-specific mortality rates in the recent past, and do not necessarily purport to be projections.