The life table is primarily a product of actuarial science. Recent advances in theoretical statistics and stochastic processes have made it possible to study the length of life from a purely statistical viewpoint, making the life table a valuable analytical tool for demographers, epidemiologists, biologists, and research workers in other fields. This paper introduced the definition of the fraction of last year of life(Ai) and presented a method of constructing a current abridged life table using Chiang's method. The results obtained are as follows: 1) The value of Ai represents the mortality pattern prevailing in the population in each interval. Since the mortality pattern hardly varies over time (although death rates do), the Ai values may be regarded as constant and may be used for the construction of abridged life tables of the subsequent years of the populations. However, the mortality patternvaries between different countries, areas and between men and women . Also, it was shown that the method in which the value of Ai as 0 .5 generally is not valid. Therefore, it was recognized that if this revised Chiang?fs method is used to construct an abridged life table, it may be simpler and theoretically correct, and is more easy to make statistical inference. We used the values of Ai in HOKKAIDO, IBARAKI, OSAKA and KUMAMOTO to construct a new abridged life table. It showed that woman of any age has a greater expectation of life than a man of the same age in these areas. We also found that average life expectancy in KUMAMOTO is longer than other three areas and women in HOKKAIDO have a greater expectation of life than IBARAKI and OSAKA
