| A | B |
| demography | the study of human populations |
| total fertility rate (TFR) | the average number of children a woman in a population will have in her lifetime. |
| replacement rate | the total fertility rate needed for a population to replace itself |
| life expectancy | the number of years a person can expect to live |
| dependency ratio | compares the number of people too young or old to work with a country's working-age population |
| baby boom | a sudden increase in the birh rate |
| pensions | a fixed amount of money paid to a retired person by a government or former employer |
| demographic transition model | model that shows how populations go through transitions or changes as a country develops its economy |
| birth rate | the number of births in the year for every thousand people in a population |
| death rate | the number of deaths in a year for every thousand people in a population |