These files provide very fine geographic detail, with summaries for areas ranging from the entire U.S. to a census block. There are dozens of geographic summary levels provided.
The original files provided from the U.S. Census Bureau had a full set of over 270 data cells for each geographic area. In processing the file the Missouri Census Data Center has attempted to provide more compact and, we hope, easier to use data summaries. Most of the data sets found here are compact summaries data sets in which each observation (row) corresponds to one geographic entity (a census tract or a county, for example) and the variables are a set of about 34 key items gleaned from the over 270 cells on the orginal summary record. In many cases, we have done aggregation to create summaries for geographic entities that were not summarized on the orginal files (for example, Metropolitan Statistical Areas for the U.S. and School Districts in Missouri.)
The data covers the entire country. We have a few more geographic units summarized for Missouri, but the basic data down to the census block level is available for all states. Generally, the coverage of each data file varies and is identified by the first two letters of the file name, which is either us or a state postal abbreviation such as mo, ca, il, etc.
Occurs only on selected data views. This was our attempt to create a single character string key that would provide a linkage to Arcview shape files being provided by various sources. These strings are just a set of geographic code values strung together.
A sequentially assigned numeric key that links the data back to the state's geos data file.
Our locally generate concatenation of geographic code separated by dashes that uniquely ID the area. Not as useful as we had hoped. Probably best to ignore it.
Geographic Summary Level code .
|SUMLEV Code||Summary Level|
|050||County (or county equivalent)|
|060||County subdivision (MCD, township, CCD)|
|140||Census tract (complete)|
|155||Place (within county)|
|500||Congressional District (106th)|
|610||State Senate District (as of 2000)|
|620||State House District (as of 2000)|
|700||VTD (Voting Tabulation District)|
|740||Block Group, split by VTD, MCD, and Place|
|750||Census Block Note: On Summary File 1, block summaries
have a SUMLEV code of '101'. |
What's the difference? Sort order, we guess. To us, a census block is a census block --
it cannot be split by anything because it is by definition the smallest thing
there is in terms of census geography.
Name of the geographic area being summarized.
FIPS state code.
State postal abbreviation.
5-digit FIPS county code. Will sometimes print as the county name because $county. format code has been permanently assigned to it.
Census tract in tttt.tt format. Leading and trailing zeroes coded. Tract codes are unique within counties and all areas are assigned a tract code.
Logical Record Number. Important when reading the orginal set of 40 files that were used to create these data sets. Not nearly as interesting here, but it does form a link back to the orginal raw data files and could be used as a link variable, though we prefer to use geo_id for that purpose.
Census state code. Rarely used any more. Use the FIPS code.
County code (3-digit version) -- See county variable, above, which is 5 characters and includes the state code.
County size code.
County subdivision (MCD) FIPS code. Unique within state. (The census 3-digit code for these entities that was unique within county and was used in earlier censuses is not included on 2000 files.) available.)
County subdivision class code.
County subdivision size code.
Place FIPS code. Unique within state. (The The census 4-digit place code that was used in earlier censuses is not included on 2000 files.) A values of 99999 is sometimes used to indicate a non-place remainder of an area, where "non-place" means not incorporated and not in a census designated place.
Place class code.
Place description code.
Place size code.
Block group. (First digit of block on block level observations.) Block groups are unique within census tracts.
Census Block. A 4-digit code this decade, the first digit being the block group. In 1990 the blocks codes were 3 digits with an optional alpha suffix. In 1970 and 1980 blocks were just 3 digits. This is the smallest geographic level that the census recognizes. Blocks are unique within census tract, which are unique within county.
Metropolitan Statistical Area/Consolidated MSA. As of Jan. 1, 2000 we think.
Metropolitan Area Size Code.
Two-digit code for CMSA.
Metropolitan area central city indicator.
New England County Metropolitan Area code. N.A. outside New England.
Urban Rural code - would be very valuable but it is NOT defined on pl94. (Maybe later we can add it.) For now, the field is always blank.
Congressional District - 106th (1998)
State Leg District Upper Chamber (Senate district in Missouri)
State Leg District Lower Chamber (House district in Missouri)
Voting Tabulation District. How these are assigned and documented varies from state to state and sometimes from county to county. Used almost exclusively in redistricting applications.
VTD indicator to indicator if it is a real or pseudo VTD.
3-digit ZCTA code - not used on pl94.
ZIP Census Tabulation Area - not used on pl94.
Land Area in Square Meters
Water Area Sq Meters
Functional Status Code.
Geographic Change User Note Indicator.
100% Population Count. Should be the same as TotPop on these files.
Internal point north latitude. Accurate to 6 decimal places.
Internal point west longitude (will be negative). Accurate to decimal places.
Legal/Statistical Area Description Code. See format code for values.
Blank for many summary levels. Where used, values are "P" to indicate an area that is split (e.g. just part of a tract or BG), or "W" to indicate this is the whole area.
Elementary school district (NCES code) This and the other 2 school codes appear on the block level summaries only. To get data by school district you have to sum data at the block level.
Secondary school district (NCES code) NA for Missouri.
Unified school district (NCES code).
Transportation Analysis Zone. This code appears on block level summaries only.
Urban growth area. Only relevant in state of Oregon.
PUMA Code as used on 5% PUMA files. NA on pl94 files.
PUMA Code as used on 1% PUMA files. NA on pl94 files.
Land Area Sq Miles - derived from value in square meters.
Total Area Sq Miles - derived from AreaLand + AreaWatr and converted to square miles.
White alone : Persons who checked the "White" option and no other in response to the race question.
White alone or in combination : Persons who checked the "White" option in response to the race question (regardless of whether or not they checked any other).
Each of the following pairs of race counts use comparable definitions, i.e. they report persons who checked only that race and persons who checked that race regardless of what else they checked.
Black alone or in combination
Amer Indian alone
Amer Indian alone or incombination
Asian alone or in combination
Hawaaian or PI alone
Hawaaian or PI alone or in combination
Some Other race alone
Some other race alone or in combination
White alone, Non Hispanic
White alone or in combination, Non Hispanic
Hispanic Population . This is not a race. On the census questionnaire, there is a question regarding race that does not have hispanic as one of the choices. Instead, there is a separate question asking if you are hispanic. Thus, a person can be both white and hispanic, or both black and hispanic.
Population Aged 18 and over.
White alone, over 18
White alone or in combination, over 18
Black alone, over 18
Black alone or in combination, over 18
AIAN alone, over 18
AIAN alone or in combination, over 18
Asian alone, over 18
Asian alone or in combination, over 18
Hawaaian or PI alone, over 18
Hawaiian or PI alone or in combination, over 18
Other race alone, over 18
Other race alone or in combination, over 18
White Non-hisp alone, over 18
White Non-hisp alone or in combination, over 18
Hispanic Pop Over 18
Multi Racial - Persons who checked more than one race.
Multi Racial Over 18