What are the different methods used for population forecasting?

There are several methods used for population forecasting, including cohort-component projection, extrapolation, and simulation modeling. Cohort-component projection involves projecting future population size and composition by age and sex based on assumptions about fertility, mortality, and migration rates. Extrapolation involves extending past trends into the future, while simulation modeling involves creating virtual populations and observing how they change over time under different scenarios. Each method has its advantages and limitations, and the choice of method depends on the availability and quality of data, as well as the specific needs of the forecasting project.