Projecting the Presence: Estimating Incomplete Parity- and Age-specific Fertility Rates

Carlo G. Camarda, Max Planck Institute for Demographic Research
Harald Wilkoszewski, Max Planck Institute for Demographic Research

Complex demographic analyses often require long-time series of detailed vital rates. In many cases, the data available do not meet these requirements: whereas crude indicators are given for long-time series, detailed rates are only available for short periods. In the area of fertility e.g. TFR are easily obtained, while parity- and age-specific fertility rates (PASFR) are often incomplete. This paper provides a new approach to deal with this kind of data structure. We suggest a modified application of the Lee Carter model (LC), which usually is being used in the area of mortality; given the fact that fertility patterns are generally speaking more erratic than mortality trends, the linear assumption in the forecast of the LC does not lead to reasonable results. Therefore, we use information given by the available TFR to project PASFR. We apply our method to East and West Germany. Data come from the MPIDR Fertility Database.