Geographic Areas for Neighborhood-Level Analysis Using ACS Data Michael Ratcliffe Geography Division US Census Bureau 1

Which census geographic areas relate to neighborhoods? Block Groups –Subsets of census tracts –Population range: 600 to 1,200 Census Tracts –Population range: 1,200 to 8,000; optimum 4,000 ZIP Code Tabulation Areas –Census block-based representations of ZIP Codes Places –Incorporated places –Census designated places (unincorporated places) 2

Data for Small Geographic Areas Block Groups2000 Census2010 Census Census Tracts2000 Census2010 Census Incorporated Places Census Designated Places 2000 Census*2010 Census2010 Census* ZIP Code Tabulation Areas No updates since 2002; not included in data 2010 Census * CDP boundaries may be modified as a result of annexations by adjacent incorporated places, or if the community incorporates.

4 Places and census tracts, Baltimore city and Baltimore County Tracts may subdivide places in densely settled areas, but will encompass multiple communities in rural areas.

5 Baltimore neighborhoods and tracts

6 Neighborhoods and tracts do not always align.

7 Block groups, tracts, and neighborhoods

8 Starr County, Texas Current places with colonias and 2010 census designated places

9 Colonias defined as CDPs, Starr County, Texas. Colonias are generally smaller than tracts and block groups.

ZIP Code Tabulation Areas and Census Tracts 10 In DC, census tracts subdivide ZIP code tabulation areas.