How do the gross reproductive rate and the net reproductive rate differ?

Gross Reproductive Rate (GRR) calculates the average number of female offspring born to a female during her reproductive lifetime, giving an overview of the potential for population growth. In contrast, Net Reproductive Rate (NRR) calculates the average number of female offspring born to a female during her reproductive lifetime, taking into account both fertility rates and the likelihood of survival to reproductive age. The main differences between GRR and NRR are: 1. GRR only considers the number of female offspring produced per woman in each age group, whereas NRR also incorporates age-specific survivorship rates of the female population. 2. GRR provides a simple measure of potential population growth, while NRR offers a more comprehensive and realistic representation of population growth potential, accounting for mortality rates before reaching reproductive age. 3. A GRR value of 1 indicates no potential for population growth or decline, while a NRR value of 1 indicates a stable population where females are exactly replacing themselves.