Fit fertility rates with Coale-Trussell parameteric fertility model $$ f_x= F\,G(x)\, n(x)\, e^{m v(x)} $$ \(G(a)\) is the first marriage distribution $$ G(a)=\int_{a_0}^a g(x) dx $$ where \(g(a)\) is the marriage rate $$ g(a) = \frac{0.19465}{k}\exp\left(-\frac{0.174}{k}(a-a_0-6.06 k) -\exp\left[-\frac{0.2881}{k}(a-a_0-6.06 k)\right]\right) $$ \(n(a)\) is the schedule of natural fertility and \(v(a)\) describes the age pattern of volentary fertility reduction through contraception or abortions. The parameters \(F\), \(a_0\), \(k\) and \(m\) are chosen to minimize the square of the absolute error in fertility rates.