censusapi is a wrapper for the United States Census Bureau’s APIs. As of 2017 over 200 Census API endpoints are available, including Decennial Census, American Community Survey, Poverty Statistics, and Population Estimates APIs. This package is designed to let you get data from all of those APIs using the same main function—getCensus—and the same syntax for each dataset.
censusapi generally uses the APIs’ original parameter names so that users can easily transition between Census’s documentation and examples and this package. It also includes metadata functions to return data frames of available APIs, variables, and geographies.
To use the Census APIs, sign up for an API key. Then, if you’re on a non-shared computer, add your Census API key to your .Renviron profile and call it CENSUS_KEY. censusapi will use it by default without any extra work on your part. Within R, run:
# Add key to .Renviron
Sys.setenv(CENSUS_KEY=YOURKEYHERE)
# Reload .Renviron
readRenviron("~/.Renviron")
# Check to see that the expected key is output in your R console
Sys.getenv("CENSUS_KEY")In some instances you might not want to put your key in your .Renviron - for example, if you’re on a shared school computer. You can always choose to specify your key within getCensus instead.
To get started, load the censusapi library.
library(censusapi)The Census APIs have over 200 endpoints, covering dozens of different datasets.
To see a current table of every available endpoint, run listCensusApis:
apis <- listCensusApis()
View(apis)
This returns useful information about each endpoint, including name, which you’ll need to make your API call.
getCensusThe main function in censusapi is getCensus, which makes an API call to a given Census API and returns a data frame of results. Each API has slightly different parameters, but there are always a few required arguments:
name: the name of the API as defined by the Census, like “acs5” or “timeseries/bds/firms”vintage: the dataset year, generally required for non-timeseries APIsvars: the list of variable names to getregion: the geography level to return, like state or countySome APIs have additional required or optional arguments, like time, monthly, or period. Check the specific documentation for your API to see what options are allowed.
Let’s walk through an example getting uninsured rates by income group using the Small Area Health Insurance Estimates API, which provides detailed annual state-level and county-level estimates of health insurance rates.
censusapi includes a metadata function called listCensusMetadata to get information about an API’s variable options and geography options. Let’s see what variables are available in the SAHIE API:
sahie_vars <- listCensusMetadata(name="timeseries/healthins/sahie", type = "variables")
head(sahie_vars)## name label
## 1 AGE_DESC Age Category Description
## 2 NUI_LB90 Number Uninsured, Lower Bound for 90% Confidence Interval
## 3 STATE State FIPS Code
## 4 NIC_MOE Number Insured, Margin of Error
## 5 NIPR_PT Number in Demographic Group for Selected Income Range, Estimate
## 6 RACECAT Race Category
## concept predicateType limit required
## 1 Demographic ID int 0 NA
## 2 Uncertainty Measure int 0 NA
## 3 Geographic ID int 0 NA
## 4 Uncertainty Measure int 0 NA
## 5 Estimate int 0 NA
## 6 Demographic ID int 0 NAWe’ll use a few of these variables to get uninsured rates by income group:
IPRCAT: Income Poverty Ratio CategoryIPR_DESC: Income Poverty Ratio Category DescriptionPCTUI_PT: Percent Uninsured in Demographic Group for Selected Income Range, EstimateNAME: Name of the geography returned (e.g. state or county name)We can also use listCensusMetadata to see which geographic levels we can get data for using the SAHIE API.
listCensusMetadata(name="timeseries/healthins/sahie", type = "geography")## name geoLevelId requires wildcard optionalWithWCFor
## 1 us 010 NULL NULL <NA>
## 2 county 050 state state state
## 3 state 040 NULL NULL <NA>This API has three geographic levels: us, county within states, and state.
First, using getCensus, let’s get uninsured rate by income group at the national level for 2015.
getCensus(name="timeseries/healthins/sahie",
vars=c("NAME", "IPRCAT", "IPR_DESC", "PCTUI_PT"),
region="us:*", time=2015)## NAME IPRCAT IPR_DESC PCTUI_PT time us
## 1 United States 0 All Incomes 10.9 2015 1
## 2 United States 1 <= 200% of Poverty 18.6 2015 1
## 3 United States 2 <= 250% of Poverty 17.8 2015 1
## 4 United States 3 <= 138% of Poverty 19.1 2015 1
## 5 United States 4 <= 400% of Poverty 15.1 2015 1
## 6 United States 5 138% to 400% of Poverty 12.8 2015 1We can also get this data at the state level for every state by changing region to "state:*":
sahie_states <- getCensus(name="timeseries/healthins/sahie",
vars=c("NAME", "IPRCAT", "IPR_DESC", "PCTUI_PT"),
region="state:*", time=2015)
head(sahie_states)## NAME IPRCAT IPR_DESC PCTUI_PT time state
## 1 Alabama 0 All Incomes 11.9 2015 01
## 2 Alaska 0 All Incomes 16.3 2015 02
## 3 Arizona 0 All Incomes 12.8 2015 04
## 4 Arkansas 0 All Incomes 11.1 2015 05
## 5 California 0 All Incomes 9.7 2015 06
## 6 Colorado 0 All Incomes 9.2 2015 08Finally, we can get county-level data. The geography metadata showed that we can choose to get county-level data within states. We’ll use region to specify county-level results and regionin to request data for Alabama and Alaska.
sahie_counties <- getCensus(name="timeseries/healthins/sahie",
vars=c("NAME", "IPRCAT", "IPR_DESC", "PCTUI_PT"),
region="county:*", regionin="state:1,2", time=2015)
head(sahie_counties, n=12L)## NAME IPRCAT IPR_DESC PCTUI_PT time state
## 1 Autauga County, AL 0 All Incomes 9.4 2015 01
## 2 Autauga County, AL 1 <= 200% of Poverty 16.8 2015 01
## 3 Autauga County, AL 2 <= 250% of Poverty 15.5 2015 01
## 4 Autauga County, AL 3 <= 138% of Poverty 18.6 2015 01
## 5 Autauga County, AL 4 <= 400% of Poverty 12.4 2015 01
## 6 Autauga County, AL 5 138% to 400% of Poverty 9.6 2015 01
## 7 Baldwin County, AL 0 All Incomes 11.5 2015 01
## 8 Baldwin County, AL 1 <= 200% of Poverty 21.1 2015 01
## 9 Baldwin County, AL 2 <= 250% of Poverty 19.5 2015 01
## 10 Baldwin County, AL 3 <= 138% of Poverty 22.5 2015 01
## 11 Baldwin County, AL 4 <= 400% of Poverty 15.7 2015 01
## 12 Baldwin County, AL 5 138% to 400% of Poverty 12.2 2015 01
## county
## 1 001
## 2 001
## 3 001
## 4 001
## 5 001
## 6 001
## 7 003
## 8 003
## 9 003
## 10 003
## 11 003
## 12 003Some geographies, particularly Census tracts and blocks, need to be specified within larger geographies like states and counties. This varies by API endpoint, so make sure to read the documentation for your specific API and run listCensusMetadata to see the available geographies.
You may want to get get data for many geographies that require a parent geography. For example, tract-level data from the 1990 Decennial Census can only be requested from one state at a time.
In this example, we use the built in fips list of state FIPS codes to request tract-level data from each state and join into a single data frame.
fips## [1] 1 2 4 5 6 8 9 10 11 12 13 15 16 17 18 19 20 21 22 23 24 25 26
## [24] 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 44 45 46 47 48 49 50
## [47] 51 53 54 55 56tracts <- NULL
for (f in fips) {
stateget <- paste("state:", f, sep="")
temp <- getCensus(name="sf3", vintage=1990,
vars=c("P0070001", "P0070002", "P114A001"), region="tract:*",
regionin = stateget)
tracts <- rbind(tracts, temp)
}
head(tracts)## state county tract P0070001 P0070002 P114A001
## 1 01 001 020100 944 917 11663
## 2 01 001 020200 917 1060 8555
## 3 01 001 020300 1451 1518 11782
## 4 01 001 020400 2166 2223 15323
## 5 01 001 020500 1604 1582 14522
## 6 01 001 020600 1784 1661 10630The regionin argument of getCensus can also be used with a string of nested geographies, as shown below.
The 2010 Decennial Census summary file 1 requires you to specify a state and county to retrieve block-level data. Use region to request block level data, and regionin to specify the desired state and county.
data2010 <- getCensus(name="sf1", vintage=2010,
vars=c("P0010001", "P0030001"),
region="block:*", regionin="state:36+county:027")
head(data2010)## state county tract block P0010001 P0030001
## 1 36 027 010000 1020 73 73
## 2 36 027 010000 1023 0 0
## 3 36 027 010000 1030 68 68
## 4 36 027 010000 1031 0 0
## 5 36 027 010000 1032 0 0
## 6 36 027 010000 1033 0 0For the 2000 Decennial Census summary file 1, tract is also required to retrieve block-level data. This example requests data for all blocks within Census tract 010000 in county 027 of state 36.
data2000 <- getCensus(name="sf1", vintage=2000,
vars=c("P001001", "P003001"),
region="block:*", regionin="state:36+county:027+tract:010000")
head(data2000)## state county tract block P001001 P003001
## 1 36 027 010000 1000 18 18
## 2 36 027 010000 1001 26 26
## 3 36 027 010000 1002 59 59
## 4 36 027 010000 1003 67 67
## 5 36 027 010000 1004 52 52
## 6 36 027 010000 1005 116 116This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.