This is data adapted from the county-level estimates of fertilizer nitrogen and phosphorus based on commercial sales from 1945 to 2012. Please visit [here](https://www.sciencebase.gov/catalog/item/5851b2d1e4b0f99207c4f238) for more details.
us_fertilizer_county
A data frame with 582012rows and 11 variables:
FIPS is a combination of state and county codes, in character format.
The state abbr. of U.S.
County name in U.S.
The land area in each county, unit: km squared
The water area in each county, unit: km squared
The latitude of centriod in each county, e.g. 32.53638
The longitude of centriod in each county, e.g. -86.64449
The quantity of fertilizeation as N or P, e.g. kg N or kg P
The year of estimated data, e.g. 1994
The fertilizer type, e.g. N or P
The land use type of fertilizer, e.g. farm and nonfarm
The input type of nutrient, e.g. Fertilizer or Manure
require(usfertilizer) data(us_fertilizer_county)