Social security family finance and demography

In this paper we analyzed a model of endogenous fertility in presence of financial market assets and social security pensions. Given the children externality and in the absence of corrective policy, the fertility rate chosen in market economy is too low. Indeed, in his optimal choice of family size, the representative household does not take into account of this children externality which leads to a sub optimal demography. We have shown that an optimal demographic allocation exists and can be implemented through a subvention taxation policy if it is available