June 2020 -- NCES has produced estimates of adults’ literacy and numeracy skills for all U.S. states and counties, which are accessible through an interactive mapping tool: https://nces.ed.gov/surveys/piaac/skillsmap
For all 50 U.S. states, all 3,141 U.S. counties, and the District of Columbia, the Skills Map provides four different estimates of the literacy and numeracy proficiency of adults (aged 16–74):
the percentage with the lowest levels of proficiency (at or below Level 1; below 226 points),
the percentage with medium proficiency (at Level 2; 226–275 points),
the percentage with the highest levels of proficiency (at or above Level 3; above 275 points), and
the average score for all adults (aged 16–74) in the state or county (on the PIAAC scale of 0–500).
The Skills Map allows users to compare the estimates of any county to those of its state or compare the estimates of any state to the national estimates. It also allows users to compare the estimates for any two counties or for any two states.
In order to help users to better understand the results produced for each state or county, the skills map gives users access to selected demographic variables from the American Community Survey (ACS). The available ACS variables provide context for the estimates by presenting basic demographic characteristics for the state or county, such as educational attainment, race/ethnicity, nativity, employment status, and poverty level.
These state and county estimates are based on combined PIAAC data collected in 2012, 2014, and 2017, and are produced using an advanced statistical method generally referred to as small area estimation (SAE). SAE is a model-dependent approach that produces indirect estimates for geographic areas where survey data are inadequate for direct estimation.