 Net reproduction rate

The mean lifetime number of offspring is the birth rate integrated against the probability of surviving to each age. For a continuous age model it is ${\int }_0^{\infty }b(a)\exp [-{\int }_0^a\mu (s)ds]da$. The Euler-Lotka equation compares this with one to locate positive population growth.

The net reproduction rate (NRR) is a demographic measure that indicates the average number of daughters that would be born to a woman (or a group of women) throughout her lifetime, assuming she experiences the exact current age-specific fertility rates and mortality rates throughout her lifetime. It provides insights into population growth or decline by accounting for both fertility and mortality among females. The net reproduction rate takes into consideration: 1. **Fecundity**: The number of daughters born per woman.