Percent Of Population That Are Non-Citizens
Currently the American Community Survey put out by the US Census Bureau estimates the number of citizens and non-citizens in each blockgroup (a group of similar demographic blocks). This map shows citizenship rates for New York State, from the 2016 ACS 5-year Averages for each Census Tract in New York State.
These estimates are used for many purposes, the most notable is for compliance with the Voting Rights Act of 1965, which requires no dilution of voting power of Citizen Voting Age Participants based on race. The Decennial Census, a full population count has not asked about Citizenship since 1950, preferring to focus on core questions to keep the form as short and easy to fill out as possible. Instead, for VRA purposes, American Community Survey estimates is used to calculating the number of citizens in each political district.
The Trump administration, in an effort to get a supposedly more accurate count of citizens and non-citizens, down to the block level, is adding the question back to the 2020 Decennial Census. Some people, worry that fewer people will fill out a longer census form or that the citizenship questions will lead minorities to not-fill out the forum. Others argue that statistically it is more accurate to estimate a large population, then it is to do a total count -- as estimates can make up for non-participation of certain groups of the population.
Data Source: 2016 ACS 5-year Average, Percentage of Non-Citizens per Census Tract. http://factfinder.census.gov/faces/nav/jsf/pages/searchresults.xhtml?refresh=t