Lightcast uses birth and mortality rates from the Center for Disease Control in the creation of population demographics data. Birth and mortality rates are used to project population counts into future years to model additions to population through births and subtractions from population due to deaths.

Births data comes from the Crude birth rates, fertility rates, and birth rates, by age, race, and Hispanic origin of mother: United States, selected years 1950–[latest] table, and deaths data comes from the Death rates for all causes, by sex, race, Hispanic origin, and age: United States, selected years 1950–[latest] table. Both are from the Health, United States annual report and can be found in the Data Finder tool.