STF 3B on CD-ROM Addendum COUNT CORRECTIONS The Census Bureau issues population count corrections on an occasional basis. Count corrections for geography at the place level and above are available from Customer Services, Data User Services Division, Bureau of the Census, Washington, DC 20233. Count corrections for geography at the census tract/BNA level or below are available from Population Division, Bureau of the Census, Washington, DC 20233. When requesting these corrections, please include the desired census tract/BNA, block group, or block numbers. USING THE FILE File Segments The file is segmented into 35 dBase III (.DBF) files, designated STF300.DBF through STF334.DBF. The STF300 segment contains the full 67 field identification section. The identification field names are shown in the Data Dictionary chapter of the technical documentation. Segments STF301 through STF334 each contain eight identification fields repeated from the STF300 segment. They are shown below. Identification Fields Common To All Segments SUMLEV Summary Level STATEFP State (FIPS) CNTY County (FIPS) SAC1 Special Area Code (1) ZIP Code SAC10 Special Area Code (10) ZIP Code Total Indicator (or Part Indicator) LOGRECNU Logical Record Number The segments are divided as shown below. Data Tables In Each Segment STF300 Field Identification Section STF301 P1 - P13 STF302 P14A - P14C STF303 P14D - P14F STF304 P14G - P14I STF305 P14J - P17 STF306 P18 - P26 STF307 P27 - P32 Data Tables In Each Segment Con. STF308 P33 - P36 STF309 P37 - P51 STF310 P52 - P60 STF311 P61 - P65 STF312 P66 - P70 STF313 P71 - P76 STF314 P77 - P83 STF315 P84 - P86 STF316 P87A STF317 P87B STF318 P87C STF319 P87D STF320 P87E STF321 P88 - P107 STF322 P107A - P118 STF323 P119 - P121 STF324 P122 - P123 STF325 P124A - P124B STF326 P125 - P143 STF327 P144 - P170, H1 - H9 STF328 H10 - H21 STF329 H22 - H33 STF330 H34 - H44 STF331 H45 - H52 STF332 H52A - H59 STF333 H60 - H81 STF334 H82 - H92 Field Names In Numeric Data Tables Fields in numeric data tables are named according to a convention which identifies the tables and the sequence of the data item within the table. The 63 data items in P88, for example, are identified as P0880001 through P0880063. The one data item in table P107A is identified as P107A001. Components Of The Field Name Character 1 P or H Character 2-4 Table number; right justified with leading zeroes Character 5 Sub-table letter; zero if not applicable Character 6-8 Item number; right justified with leading zeroes Record Identification Each record for STF 3B is uniquely identified by a combination of geographic (for example State and county), summary level, and geographic component codes. For example, if you have an STF 3B file and want to look at data for ZIP Code 20748 that is located in Prince George's County, Maryland, four identification fields must be checked: the summary level code for county records (820); special area code (1) for ZIP Code 20748; special area code (10) to determine if the ZIP Code is in more than one county; and the geographic component code. (All records will have a geo- graphic component code of 00 which indicates that data are available forthe total geographic area.) See the Summary Level Sequence Charts and Special Area Codes sections that follow for further information. SUMMARY LEVEL SEQUENCE CHARTS AND GEOGRAPHIC AREA COMPONENT CODES The Summary Level Sequence Charts chapter and the geographic area component codes provide important information for using the 1990 census summary tape files. For STF 3B, only summary levels 800 and 820 are used. The Summary Level Sequence Charts chapter for STF 3 files identifies the geographic levels for which data are provided. It is easy to determine this if you remember that the last geographic area type listed in the sequence identifies the geography of the summary level; the prior codes simply define the hierarchy. For example, in summary level 820, the hierarchy listed is ZIP Code State county. The record actually contains data for a county (or part of a county) within a given State and ZIP Code. When reading the Summary Level Sequence Charts chapter, it is important to recognize that dashes ( ) separate the individual hierarchies while slashes (/) separate different types of geography within the same hierarchy. After identifying the summary level code, turn to chart 1 at the end of this chapter to determine the geographic area codes and area characteristics provided on CD-ROM for this summary level. Remember that an asterisk (*) indicates a code in that field. The code may be one of the standard codes described below. The Summary Level Sequence Charts chapter also provides geographic component code information. This code identifies the various geographic components for which the record is repeated within the summary level. These component codes are provided in the data dictionary beginning in position 14. For example, the Summary Level Sequence Chart for STF 3B indicates that the summary level for county records (820) has geographic component codes 00. By turning to the geographic component variable in the data dictionary, you can determine that the tables for summary level 820 (county) are available for total geography (county) (geographic component=00). In short, always check the geographic codes, the summary level (beginning in position 11 of the data dictionary), the geographic component code (beginning in position 14 of the data dictionary), special area code (1), and special area code (10) for complete identification of an STF 3B record. SPECIAL AREA CODES Special area codes appear in the geographic area codes portion of the data dictionary (positions 142-171) on all STF's. The codes represented may vary across STF's. In STF 3B CD-ROM files special area code (1), and special area code (10) are used. The codes are described below. In STF 3B files only, special area code 1 is used to contain the 5-digit ZIP Code. Special area code (10) is used to indicate the total ZIP Code area or a part of a ZIP Code area. The codes used in special area code (10) are: 1 Represents the ZIP Code total Blank Represents a county part for a ZIP Code A record with SUMLEV = "820" and SAC10 = "1" represents the ZIP Codetotal. A record with SUMLEV = "800" represents the ZIP Code total and SAC10 will always = "1". Records with SUMLEV = "820" may represent county parts for that ZIP Code, and those records will also have SAC10 = "blank". Summary Level 820 may or may not contain the total data for a ZIP Code. To determine this, check special area code (10) for a code of "1" or "blank". For example: Record SUMLEV CNTY SAC1 SAC10 1 820 001 10001 1 2 800 10002 1 3 820 001 10002 Blanks 4 820 002 10002 Blanks Record 1 represents the ZIP Code total for Zip Code 10001. Record 2 represents the ZIP Code total for ZIP Code 10002, and records 3 and 4 represent the two counties for which there are data for ZIP Code 10002. Note that record 2 does not have a county code because summary level 800 will always contain data for the entire ZIP Code. STANDARD CODES In the identification section of all STF's, there are standard codes, undefined in the data dictionary, that have identical meaning regardless of the field. The codes are the same size as the field; that is, a three- character field will have three symbols. These standard codes are listed below. ! Not available The code would be shown except it had not been determined when the files were prepared (for example, metropolitan area code on a county summary level (050) on STF 1A). 9 Not in This indicates a "remainder of" an area, such as a place code in the portion of a county subdivision not in a place, or the summary level is not part of any area to which the code field applies, such as a summary level which is not in an Alaska Native Regional Corporation. Blank Not applicable This indicates that the code is not applicable to the summary level. Where these codes are specifically defined in the data dictionary, the defined code should be used. For example, in the division code description on the data dictionary (position 89), the code for the Pacific Division is indicated as "9." This "9" should be interpreted as the division code, not as "not in," the standard code for "9."