README
                     Census 2000 Summary File 1 Supplement Delivered via FTP

Contents
File Description
About the FTP Application
File Naming Conventions
Technical Documentation
Data Records and Segmentation
File Record Layout
FTP File Transfer
Spreadsheet and Data Base Aids


FILE DESCRIPTION

The SF 1 Supplement file is being created for three reasons: (1) to provide users with 
urban/rural data at the block level (not available on the Summary File 1 State files), 
(2) to provide users and American FactFinder with a source for updating SF1 tables P2 and 
H2 with urban and rural summary counts for all SF1 state summary levels, and (3) to 
provide users with SF1 tables P2 and H2 for three summary levels (085, 090, and 100) that 
were not available prior to urban/rural delineation. 


ABOUT THE FTP APPLICATION

-- The application is intended for experienced users of census data and 
   spreadsheet/database software. 

--  FTP users should have a fast file transfer capability. 

--  Users of the FTP application need to download the file and then import it into the 
    spreadsheet/database software of their choice for data analysis and table 
    presentation.

FILE NAMING CONVENTIONS 

--  The naming convention for geographic header files is ssgeo.ur1.

  -- ss is USPS state abbreviation

    --  The codes are in technical documentation on page 7-1, located at 
        http://www.census.gov/prod/cen2000/doc/sf1.pdf

  --  ssgeo.ur1 is a constant across SF1 Supplement geographic header names.

--  Naming convention for SF1 Supplement data files is ss00001.ur1.

  --  ss is USPS state abbreviation

  --  .ur1 is a constant across SF1 Supplement data file names

TECHNICAL DOCUMENTATION

--  The complete technical documentation for SF1 is available at 
    http://www.census.gov/prod/cen2000/doc/sf1.pdf . 

DATA RECORDS AND SEGMENTATION

--  Table distribution across data files is as follows:

                                       Number of              Matrix
     File name                         data items             number

     ss00001.ur1                           12                  P2-H2

---------------------------------------------------------------------

--  Five fields are carried over from the geographic header file into each data file. 

  --  These fields are file identification (FILEID) uSF1UR, 
      characteristic iteration (CHARITER), characteristic iteration file sequence number 
      (CIFSN) and logical record number (LOGRECNO). 

  --  These five fields appear in the geographic header record are in a fixed field 
      format.  These five fields appear in the data file in a comma delimited format.

  --  These five fields are used to "match" records in the data file for a particular
      characteristic iteration to the geographic information in the geoheader.  

  --  A file set structure schematic appears below:

-----------------------------------------------------------------

        Figure 2-1a. File Set Structure Schematic - File Set 

      Geographic Header File                              File 01
      File name=algeo.ur1                   File name=al00001.ur1
      ----------------------                ---------------------
      Record 1                                    FILEID (uSF1UR)
      FILEID (uSF1UR)                                 STUSAB (AL)
      STUSAB (AL)                                  CHARITER (000)
      CHARITER (000)                                   CIFSN (01)
      CIFSN (00)                                         LOGRECNO
      LOGRECNO                                          (0000001)
      (0000001)                                Table P2 (6 cells)
      Remainder of geographic header           Table H2 (6 cells)
      record for geographic area x
                                                  FILEID (uSF1UR)
      Record 2                                        STUSAB (AL)
      FILEID (uSF1UR)                              CHARITER (000)
      STUSAB (AL)                                      CIFSN (00)
      CHARITER (000)                                     LOGRECNO
      CIFSN (00)                                        (0000002)
      LOGRECNO                                 Table P2 (6 cells)
      (0000002)                                Table H2 (6 cells)
      Remainder of geographic header
      record for geographic area y

------------------------------------------------------------------

FILE RECORD LAYOUT

--  For a layout of the table in each file, see the following:  

    There are two tables in the SF1 Supplemental Tabulation.

    P2: Urban and Rural [6]
        Universe: Total Population
          Total:
            Urban:
              Inside urbanized areas:
              Inside urban clusters
            Rural
            Filler

    H2: Urban and Rural [6]
        Universe: Housing Units
          Total:
            Urban:
              Inside urbanized areas:
              Inside urban clusters
            Rural
            Filler


FTP FILE TRANSFER 

--  Summary File 1 (SF1) Supplement FTP directory is at 
    ftp2.census.gov/census_2000/datasets/Summary_File_1_Supplement . 

  --  Each state directory provides all files available for the identified state. 

  --  The directory for each state has a geographic header file and 1 data file. 

  --  The files are in a flat ASCII format.

  --  No software is provided.

--  Downloading multiple files

  --  UNIX environment-"mget" subcommand allows transfer of multiple files using the 
      wildcard character. 

    --  Example:  ftp> prompt off
                  ftp>mget ne*  (for this example, Nebraska is selected). 

  --  Windows Environment-many FTP products have been developed which have the capability 
      to download multiple files with a single command.  

  --  We used the ws_ftp product in testing the download.

      --  A demonstration copy is available at http://www.ipswitch.com/  . 

  --  An Internet search using the term "download multiple files" yielded other similar 
      products.  

  --  For step-by-step instructions with screen shots, please see 
      http://www.census.gov/support/2000/SF1/  


SPREADSHEET AND DATA BASE AIDS

--  For step-by-step instructions with screen shots for moving the data and structure to 
    a spreadsheet, please see http://www.census.gov/support/SF1ASCII.html .  

--  Structure files in Access97 and other formats are available at 
    http://www.census.gov/support/2000/SF1/ .  

--  We are unable to provide one-on-one support for applications of the data to specific
    spreadsheets or data base software.