Fetch USA ACS Reference Population On-Demand

fetchACSReference(years, survey = "acs5", census_api_key = NULL)

Arguments

years: Integer or vector of integers. ACS year(s) (e.g., 2020, or 2021:2023)
survey: Character. Survey type: "acs5" (default) or "acs1"
census_api_key: Character. Census API key. If NULL (default), uses CENSUS_API_KEY environment variable. Warns if neither provided.

Value

StandardizationReference object

Details

Fetches American Community Survey (ACS) estimates from Census API. Requires tidyCensus package and valid Census API key.

Note: ACS provides age-grouped estimates (not single-year). When multiple years are requested, data is combined into a single reference with year column.

Examples

if (FALSE) {
  # Option 1: Single year with environment variable key
  # Sys.setenv(CENSUS_API_KEY = "your_key_here")
  acs_2020 <- fetchACSReference(2020)

  # Option 2: Single year with direct key parameter
  acs_2020 <- fetchACSReference(2020, census_api_key = "your_key_here")

  # Option 3: Multiple years (combined into one reference)
  acs_2021_2023 <- fetchACSReference(2021:2023, survey = "acs5")

  # Use in standardization
  result <- standardizePrevalence(
    prevalenceData = my_data,
    referencePopulation = acs_2020
  )
}