A mortality table is a table of expected survivors at each age, given an assumed number of survivors at the starting age for the table. A mortality table is based on the mortality experience of a large sample of people.
For example, the first lines of the Table 80CNSMT mortality table look like this:
Age Survivors
0 100000
1 98740
2 98648
A mortality table can be used to compute life expectancies or the probability that a person of a certain age will live to achieve a certain older age. For example, the likelihood that someone age 1 will survive to age 2 according to the 80CNSMT mortality table is 98648/98740 or 99.9068%.