US census population estimates by county for 2015.
The data is formatted for easy merging with output from us_map.
data(countypop)A data frame with 3142 rows and 4 variables.
fips The 5-digit FIPS code corresponding to the county.
abbr The 2-letter state abbrevation.
county The full county name.
pop_2015 The 2015 population estimate (in number of people)
for the corresponding county.