MODIFICATION OF COALE-KISKERS EXTRAPOLATION METHOD FOR LIFE TABLES

The Coale Kisker's method of extrapolation of age-specific death rates at age 85 and more, is modified to avoid crossover with female death rates at the higher age. The modification is made on the following assumptions; (1) the value of the parameter 's' in a given populatioon is identical for both sexes, (2) the death rate at 120 is equal to 2, (3) extrapolation is based on empirical values of death rates at ages from 74 to 84. Formulas are written in terms of the exponential-quadratic function. The modified method was verified on life tables of 2002, estimated for Poland and voivodeships.