This data set has the format used by geographic identifier files in the American Community Survey (ACS) 5-year summary file. The data and documentation for the 5 years ending in year X is typically available by December of the year X+1, so 2015-2019 was available by Dec 2020.
Format
A data.frame
'data.frame': 53 obs. of 5 variables:
$ varname : chr "FILEID" "STUSAB" "SUMLEVEL" "COMPONENT" ...
$ description: chr "Always equal to ACS Summary File identification" "State Postal Abbreviation" "Summary Level" "Geographic Component" ...
$ size : num 6 2 3 2 7 1 1 1 2 2 ...
$ start : num 1 7 9 12 14 21 22 23 24 26 ...
$ type : chr "Record" "Record" "Record" "Record" ...
Source
Table found in given year dataset, info at https://www.census.gov/programs-surveys/acs/library/handbooks/geography.html https://www.census.gov/programs-surveys/acs/data/data-via-ftp.html https://www2.census.gov/programs-surveys/acs/summary_file/2020/data/5_year_entire_sf/2020_ACS_Geography_Files.zip