Contents
How many people live in a block group?
Block Groups (BGs) are statistical divisions of census tracts, are generally defined to contain between 600 and 3,000 people, and are used to present data and control block numbering.
How are census block group boundaries determined?
Blocks can be bounded by visible features—such as streets—or by invisible boundaries, such as city limits. Census blocks are often the same as ordinary city blocks. Census blocks change every decade. Census data may be provided in the form of boundaries (polygons) or centroids (points).
Do census tracts repeat?
For example, in 2010, Beaver was used as the name of 45 different county subdivisions. Places stay within state boundaries. Many place names repeat throughout the country (e.g. Kansas City, Kan. Census tracts must stay within a county and therefore a state.
How many census blocks are there in the United States?
A wall-to-wall coverage across the entire territory of the United States, Puerto Rico, and the Island Areas. Numbered uniquely with a four-digit census block number ranging from 0000 to 9999 nesting within each census tract, which nest within state and county.
How are census blocks used in legislative redistricting?
BAFs are among the geographic products provided to states and other data users containing the small area census data necessary for legislative redistricting. 2010 Census Block Relationship files are provided as a tool to help data users compare the universe of Census 2000 blocks to the universe of 2010 Census blocks.
What happens when a census block is split?
They may be split when a change in another geographic boundary occurs, such as an incorporated place annexation. If a block is split in between decades, a suffix will be added to the block number. For example, block 1000 would become block 1000A and 1000B.
How is census data different from public data?
Compared to their public use counterparts, the internal data files include more detailed geographic information, generally to the block level for the Decennial Census and census-tract level for surveys, as well as less restrictive top-coding.