Extent of fertility and migration needed for the stable development of the population of the Czech Republic in this century

Is foreign migration able to compensate the low fertility and to prevent the population decrease and the population ageing? It has been demonstrated that the annual number of immigrants needed to restrict the decline in the population size is relatively small while the number of immigrants preventing the population ageing had to be unrealistically high. The article shows, which extent of migration would be necessary to stabilize the size and the sex-and-age structure of the population of the Czech Republic in the sense of the convergence to the modified stationary population model which assumes decrease in the number of live births corresponding to the decreasing mortality. While in the case of increase in fertility the annual numbers of migrants necessary for the convergence are relatively small, in the case of stabilizing fertility at the present low level the numbers of migrants seem to be unrealistically high.