Editing Census tract (section)

===United States===
The concept of the census tract was first developed in the United States. In 1906, Walter Laidlaw originated the concept of permanent, small geographic areas as a framework for studying change from one decennial [[United States Census]] to another in neighborhoods within [[New York City]].<ref name="Krieger">{{cite journal|last=Krieger|first=Nancy|year=2006|title=A century of census tracts: Health & the body politic (1906–2006)|journal=Journal of Urban Health|volume=83|issue=3|pages=355–361|doi=10.1007/s11524-006-9040-y|pmc=2527201|pmid=16739037}}</ref> For the [[United States Census, 1910|1910 Census]], eight cities—New York, [[Baltimore]], [[Boston]], [[Chicago]], [[Cleveland]], [[Philadelphia]], [[Pittsburgh]], and [[St. Louis]]—delineated census tracts (then termed ‘‘districts’’) for the first time. No additional jurisdictions delineated census tracts until just prior to the [[United States Census, 1930|1930 Census]], when an additional ten cities chose to do so. The increased interest in census tracts for the 1930 Census is attributed to the promotional efforts of Howard Whipple Green, who was a statistician in Cleveland, [[Ohio]], and later the chairman of the American Statistical Association's Committee on Census Enumeration Areas. For more than 25 years, Green strongly encouraged local citizens, via committees, to establish census tracts and other census statistical geographic areas. The committees created by local citizens were known as Census Tract Committees, later called Census Statistical Areas Committees.
 
After 1930, the Census Bureau saw the need to standardize the delineation, review, and updating of census tracts and published the first set of census tract criteria in 1934. The goal of the
criteria has remained unchanged; that is, to assure comparability and data reliability through the standardization of the population thresholds for census tracts, as well as requiring that their
boundaries follow specific types of geographic features that do not change frequently. The Census Bureau began publishing census tract data as part of its standard tabulations beginning with
the [[United States Census, 1940|1940 Census]]. Prior to that time, census tract data were published as special tabulations.

For the 1940 Census, the Census Bureau began publishing census block data for all cities with 50,000 or more people. [[Census block]] numbers were assigned, where possible, by census
tract, but for those cities that had not yet delineated census tracts, ‘‘block areas’’ (called ‘‘block numbering areas’’ [BNAs] in later censuses) were created to assign census block numbers.
Starting with the [[United States Census, 1960|1960 Census]], the [[United States Census Bureau|Census Bureau]] assumed a greater role in promoting and coordinating the delineation, review, and update of census tracts. For the [[United States Census, 1980|1980 Census]], criteria for BNAs were changed to make them more comparable in size and shape to census tracts. For the [[United States Census, 1990|1990 Census]], all counties contained either census tracts or BNAs.

[[United States Census, 2000|Census 2000]] was the first decade in which census tracts were defined in all counties. In addition, the Census Bureau increased the number of geographic areas whose boundaries could be used as census tract boundaries. It also allowed tribal governments of federally recognized [[American Indian tribes]] with a reservation and/or off-reservation trust lands to delineate tracts without regard to State and/or county boundaries, provided the tribe had a 1990 Census population of at least 1,000.<ref>{{cite web |url=https://www.census.gov/geo/www/psap2010/tract_criteria.pdf |title=Census Tract Program for the 2010 Decennial Census—Final Criteria | work=Federal Register |publisher=U. S. Census Bureau |date=2008-05-14|access-date=2008-10-14}}</ref>

Census tracts are also used by the [[Small Business Administration]] to define boundaries of [[HUBZone]]s.