Description of the data source, numerator, denominator, survey questions, and other relevant details about the national estimate.
Number of deaths of infants aged 28 days to less than 1 year
Number of live births
To create linked data files, death certificates are linked with corresponding birth certificates for infants who die in the U.S. before their first birthday. The linked file is used for calculating infant mortality rates by mother's race and ethnicity because these variables are more accurately collected on the birth certificate than the death certificate.
Depending upon county population size, the period county percent for the most recent 3, 5, or 10 years is reported.
Additional resources about the objective