A census block is the smallest geographic unit used by the United States Census Bureau for tabulation of 100-percent data (data collected from all houses, rather than a sample of houses). Several blocks make up block groups, which again make up census tracts. There are on average about 39 blocks per block group, but there are variations. Blocks typically have a four-digit number, where the first number indicates which block group the block is in. For example, census block 3019 would be in block group 3. The number of blocks in the United States, including Puerto Rico, is about 8,200,000.
Blocks are typically bounded by streets, roads or creeks. In cities, a census block may correspond to a city block, but in rural areas where there are fewer roads, blocks may be limited by other features. The population of a census block varies greatly. There are about 2,700,000 blocks with a population of 0, while a block that is entirely occupied by an apartment complex might have several hundred inhabitants.
Census blocks covering the entire country were introduced with the 1990 census. Prior to this, back to the 1940 census, only selected areas were divided into blocks.
Famous quotes containing the word block:
“Only he who can view his own past as an abortion sprung from compulsion and need can use it to full advantage in the present. For what one has lived is at best comparable to a beautiful statue which has had all its limbs knocked off in transit, and now yields nothing but the precious block out of which the image of one’s future must be hewn.”
—Walter Benjamin (1892–1940)