The TFR and birth control]

Total fertility rate if (TFR) is a simple an straight forward measure of women's fertility. However, it is difficult to use the TFR as a target measure in FP programs. If TFR level is set as a target for a particular year, how can women's fertility be regulated to achieve this target? The following analysis suggests a simple model to control the proportion of birth parity. First, the TFR is decomposed into a parity- specific TFR. The parity-specific TFR can be worked out using coefficients of the regression models calculated from data of previous fertility surveys. Once the TFR is given, the parity-specific total fertility can be calculated using a model with coefficients from empirical data. Then the number of births of each parity may be calculated from the parity-specific TFR using the female age structure in a particular year, the survival probability, and the standard fertility model for each parity. When the number of surviving children of each women at child-bearing age is known, the desired proportion of births of each parity can be calculated using the standard birth probability during a years. From these models, it would be possible to calculate how many women can have their first child/year, and how many can have the second. Thus, family planning organizations would be in a position to formulate a birth quota on the basis of the above information.