Census 2000 TIGER/Line(R) Files Technical Documentation Appendix C-Changes in the TIGER/Line File Versions Field Name Changes The following are the field name changes that occurred between versions of the TIGER/Line(R) files. Record Type 1999 Version 2000 Version Record Type 1 TRACT90L TRACTL TRACT90R TRACTR BLOCK90L BLOCKL BLOCK90R BLOCKR Record Type 1998 Version 1999 Version Record Type 1 FAIRL AIANHHL FAIRR AIANHHR TRUSTL AIHHTLIL TRUSTR AIHHTLIR FMCDL COUSUBL FMCDR COUSUBR FSMCDL SUBMCDL FSMCDR SUBMCDR FPLL PLACEL FPLR PLACER CTL TRACT90L CTR TRACT90R BLKL BLOCK90L BLKR BLOCK90R Record Type 3 COUN90L COUNTY90L COUN90R COUNTY90R FMCD90L COUSUB90L FMCD90R COUSUB90R FPL90L PLACE90L FPL90R PLACE90R CTBNA90L TRACT90L CTBNA90R TRACT90R AIR90L AIANHHCE90L AIR90R AIANHHCE90R TRUST90L AIHHTLI90L TRUST90R AIHHTLI90R BLK90L BLOCK90L BLK90R BLOCK90R AIRL AIANHHCEL AIRR AIANHHCER FANRCL ANRCL FANRCR ANRCR CENSUS3 AITSCEL CENSUS4 AITSCER RS2, VTD90L, and VTD90R AITSL and AITSR Record Type 5 STATE and COUNTY FILE Record Type 7 STATE and COUNTY FILE Record Type 8 STATE and COUNTY FILE Record Type 9 STATE and COUNTY FILE Record Type A STATE and COUNTY FILE FAIR AIANHH90 FMCD COUSUB90 FPL PLACE90 CTBNA90 TRACT90 BLK90 BLOCK90 UA PUMA1 URBFLAG UR90 CTPP RS5 COUN90 COUNTY90 AIR90 AIANHHCE90 Record Type C FIPSYR DATAYR PDC PLACEDC LASAD LSADC AIR AIANHHCE VTD VTDTRACT UA UAUGA ANRC and CENSUS5 AITSCE CENSUS5 and NAME NAME Record Type H STATE and COUNTY FILE Record Type I STATE and COUNTY FILE Record Type P STATE and COUNTY FILE Record Type R STATE and COUNTY FILE Record Type S STATE and COUNTY FILE CMSA MSACMSA MA PMSA FAIR AIANHH AIR AIANHHCE TRUST AIHHTLI ANRC RS6 FCCITY CONCIT FMCD COUSUB FSMCD SUBMCD FPL PLACE CT TRACT BLK BLOCK STSENATE SLDU STHOUSE SLDL CENSUS7 UGA RS7 BLKGRP COUNCOL COUNTYCOL BLKCOL BLOCKCOL ZCTA ZCTA5 Record Type 1997 Version 1998 Version Record Type 1 CTBNAL CTL CTBNAR CTR Record Type 3 RS2 FANRCL RS3 FANRCR RS4 CENSUS3 RS5 CENSUS4 VTDL VTD90L VTDR VTD90R Record Type A RS1 UA UA UA90 Record Type C FIPSYR expanded to four characters affecting all fields on Record Type C NAME ANRC, CENSUS5, and NAME Record Type S CMSAMSA CMSA PMSA MA STATECU STATE COUNTYCU COUNTY CTBNA00 CT BLK00 BLK RS10 CENSUS6 STSENATE and STHOUSE STSENATE, STHOUSE, and CENSUS7 VTD00 VTD RS11, RS12, RS13, RS14, and FILLER STATECOL, COUNCOL, BLKCOL, BLKSUFCOL, ZCTA, and RS8 Record Type 1995 Version 1997 Version Record Type 3 RS1, RS2, RS3, and RS4 AIR90L, AIR90R, TRUST90L, TRUST90R, and RS1 RS5, RS6, ANRCL, and ANRCR RS2 and RS3 RS7 and RS8 RS4, RS5, and RS6 Record Type A SDMID RS1 RS9 STATE90, COU90, and AIR90 Record Type C ANRC, CMSAMSA, and PMSA ENTITY, MA, and SD Record Type 1994 Version 1995 Version Record Type 1 CTBNA90L CTBNAL CTBNA90R CTBNAR BLK90L BLKL BLK90R BLKR Record Type S CTBNA90 CTBNA00 BLK90 BLK00 Record Type 1990 Version 1992 Version 1994 Version Record Type 1 SIDE1 1SIDE SIDE1 FRIADDFL FRIADDL TOIADDFL TOIADDL FRIADDFR FRIADDR TOIADDFR TOIADDR AIRR FAIRR ANRCL TRUSTL and TRUSTR ANRCR CENSUS1 and CENSUS2 CTBNAL CTBNA90L CTBNAR CTBNA90R BLKL BLK90L BLKR BLK90R Record Type 3 80STATEL STATE80L STATE90L 80STATER STATE80R STATE90R 80COUNL COUN80L COUN90L 80COUNR COUN80R COUN90R 80FMCDL FMCD80L FMCD90L 80FMCDR FMCD80R FMCD90R 80FPLL FPL80L FPL90L 80FPLR FPL80R FPL90R 80CTBNAL CTBNA80L CTBNA90L 80CTBNAR CTBNA80R CTBNA90R 80BLKL BLK80L RS1 80BLKR BLK80R RS2 80MCDL MCD80L RS3 80MCDR MCD80R RS4 80PLL PL80L BLK90L 80PLR PL80R BLK90R MCDL RS5 MCDR RS6 SMCDL ANRCL SMCDR ANRCR PLL RS7 PLR RS8 Record Type 6 FRIADDFL FRIADDL TOIADDFL TOIADDL FRIADDFR FRIADDR TOIADDFR TOIADDR Record Type 7 LONG LALONG LAT LALAT Record Type A CTBNA CTBNA90 BLK BLK90 CD101 CD106 CD103 CD108 RS CTPP and RS Record Type I RTPOINT RTLINK POLYL POLYIDL POLYR POLYIDR Record Type P LONG POLYLONG LAT POLYLAT Redistricting Census 2000 TIGER/Line Files The Redistricting Census 2000 version of the TIGER/Line files was the official version of the TIGER/Line files delivered to the official recipients under Public Law 94-171 and to redistricting officials in the District of Columbia and the Commonwealth of Puerto Rico. That version of the TIGER/Line files contained the Census 2000 geographic entities required for redistricting and other uses, and included the Census 2000 tabulation block numbers, and the final Census 2000 definitions of the census tracts, census designated places (CDPs), voting districts, state legislative districts, school districts, and so forth. The only Census 2000 geographic entities this version of the TIGER/Line files did NOT contain were the ZIP Code Tabulation Areas (ZCTAs(TM)) and the Census 2000 urban areas, and the address ranges appearing in the Redistricting Census 2000 TIGER/Line files were of approximately the same vintage as those appearing in the 1999 TIGER/Line files. That is, the U.S. Census Bureau produced the Redistricting Census 2000 TIGER/Line files in advance of the computer processing that ensured that the address ranges in the TIGER/Line files agreed with the final Master Address File (MAF) used for tabulating Census 2000. No record types were added or deleted between the 1999 and Redistricting Census 2000 versions of the TIGER/Line files. However, Census 2000 geography replaced the 1990 and current geography that appeared in the 1999 and earlier versions of the TIGER/Line files. The Redistricting Census 2000 TIGER/Line files retained the 1990 geographic entity codes on Record Types 3 and A. Field Definition Changes Four field names were changed on Record Type 1. The TRACT90L and TRACT90R fields were renamed TRACTL and TRACTR. BLOCK90L and BLOCK90R became BLOCKL and BLOCKR. The geographic entity codes on Record Types 1 and S now represented Census 2000 geography rather than 1990 or current geography. Record Types 3 and A retained the 1990 geographic entity codes although some fields on Record Type 3 were changed to contain Census 2000 geographic entity codes. 1999 TIGER/Line Files No record types were added or deleted between the 1998 and 1999 versions of the TIGER/Line files. However, there were some field name, file name, and content changes. Field names in the 1999 TIGER/Line files were updated to be consistent with the field names that are part of the geographic header used in all Census 2000 data files including the Summary Files. The U.S. Census Bureau also revised the source codes that identified for users the original source of each line feature. The U.S. Census Bureau used an early version of the 1999 TIGER/Line files to exchange data with local partners participating in U.S. Census Bureau programs. Data users were advised NOT to use the information contained in fields identified as 2000 (TENTATIVE) as the Census 2000 geographic codes because the data was subject to change. Fields identified as 2000 (TENTATIVE) were intended for use by program participants only. Field Definition Changes On several record types the Census Bureau merged the FIPS State Code for File and FIPS County Code for File fields into one field called File Code with a field name of FILE. This change affected Record Types 5, 7, 8, 9, A, H, I, P, R, and S. Fourteen field names changed on Record Type 1. The FIPS 55 Code (American Indian/Alaska Native Area), Current Left and FIPS 55 Code (American Indian/Alaska Native Area), Current Right became FIPS 55 Code (American Indian/Alaska Native Area/Hawaiian Home Land), Current Left and FIPS 55 Code (American Indian/Alaska Native Area/Hawaiian Home Land), Current Right. Their field names were changed from FAIRL and FAIRR to AIANHHL and AIANHHR. Although Hawaiian Home Land codes appeared in these fields in the 1999 TIGER/Line files, Census 2000 was the first census for which Hawaiian Home Land data was available from the U.S. Census Bureau. The American Indian Trust Land Flag, Current Left and American Indian Trust Land Flag, Current Right became American Indian/Hawaiian Home Land Indicator, Current Left and American Indian/Hawaiian Home Land Indicator, Current Right. Their field names changed from TRUSTL and TRUSTR to AIHHTLIL and AIHHTLIR. Field names FMCDL and FMCDR were changed to COUSUBL and COUSUBR. FSMCDL and FSMCDR were renamed SUBMCDL and SUBMCDR. FPLL and FPLR were renamed PLACEL and PLACER. CTL and CTR became TRACT90L and TRACT90R, and BLKL and BLKR were renamed BLOCK90L and BLOCK90R. On Record Type 3 the Census Use 3 and 4 fields were replaced by Census American Indian Tribal Subdivision Code, 2000 (TENTATIVE) Left and Census American Indian Tribal Subdivision Code, 2000 (TENTATIVE ) Right with field names AITSCEL and AITSCER. Deleted from Record Type 3 are the Voting District Code, 1990 Left and Voting District Code, 1990 Right fields and the Reserved Space 2 field. These fields were replaced by FIPS 55 Code (American Indian Tribal Subdivision), 2000 (TENTATIVE) Left occupying columns 102 through 106 and FIPS 55 Code (American Indian Tribal Subdivision), 2000 (TENTATIVE) Right occupying columns 107 through 111. The field names for these fields were AITSL and AITSR. The Census American Indian/Alaska Native Code, 1990 Left and Census American Indian/Alaska Native Code, 1990 Right fields on Record Type 3 became Census Code (American Indian/Alaska Native Area/Hawaiian Home Land), 1990 Left and Census Code (American Indian/Alaska Native Area/Hawaiian Home Land), 1990 Right. Their field names changed from AIR90L and AIR90R to AIANHHCE90L and AIANHHCE90R. The American Indian Trust Land Flag, 1990 Left and American Indian Trust Land Flag, 1990 Right became the American Indian/Hawaiian Home Land Trust Land Indicator, 1990 Left and American Indian/Hawaiian Home Land Trust Land Indicator, 1990 Right. The field names changed from TRUST90L and TRUST90R to AIHHTLI90L and AIHHTLI90R. The Census American Indian/Alaska Native Area Code, Current Left and Census American Indian/Alaska Native Area Code, Current Right became Census Code (American Indian/Alaska Native Area/Hawaiian Home Land), Current Left and Census Code (American Indian/Alaska Native Area/Hawaiian Home Land), Current Right. The field names changed from AIRL and AIRR to AIANHHCEL and AIANHHCER. Although Hawaiian home land codes appeared in the current fields in the 1999 TIGER/Line files, Census 2000 was the first census for which Hawaiian home land data was available from the U.S. Census Bureau. The U.S. Census Bureau renamed most of the field names on Record Type 3. COUN90L and COUN90R became COUNTY90L and COUNTY90R, FMCD90L and FMCD90R became COUSUB90L and COUSUB90R, FPL90L and FPL90R were renamed PLACE90L and PLACE90R, CTBNA90L and CTBNA90R became TRACT90L and TRACT90R, BLK90L and BLK90R were renamed BLOCK90L and BLOCK90R, and FANRCL and FANRCR became ANRCL and ANRCR. On Record Type A, the Census Urbanized Area Code, 2000 field (which was blank) became Public Use Microdata Area File, 1990 with a field name of PUMA1. The PUMA1 field was blank in the 1999 TIGER/Line files. The 1990 Traffic Analysis Zone codes were replaced by the 2000 (TENTATIVE) codes. The Census Transportation Planning Package Area Code field was eliminated and replaced by Reserved Space 5. The FIPS 55 Code (American Indian/Alaska Native Area), 1990 became FIPS 55 Code (American Indian/Alaska Native Area/Hawaiian Home Land), 1990. Its field name changed from FAIR to AIANHH90. The Census American Indian/Alaska Native Area Code, 1990 became the Census Code (American Indian/Alaska Native Area/Hawaiian Home Land), 1990. The field name changed from AIR90 to AIANHHCE90. No Hawaiian Home Land codes appear in these fields in the 1999 TIGER/Line files as Census 2000 was the first census for which Hawaiian Home Land data was available from the U.S. Census Bureau. Several other field names were changed on Record Type A. FMCD became COUSUB90, FPL was renamed PLACE90, CTBNA90 became TRACT90, BLK90 was changed to BLOCK90, URBFLAG was renamed UR90, and COUN90 became COUNTY90. The Census Bureau deleted the Census Alaska Native Regional Corporation Code from Record Type C. Alaska Native Regional Corporation records still appear in Record Type C with an Entity Type Code of W, but use only FIPS codes. The columns formerly occupied by the Census Alaska Native Regional Corporation Code, along with the Census Use 5 and Name fields on Record Type C were reconfigured. New to Record Type C is the American Indian Tribal Subdivision Code, with a field name of AITSCE, occupying columns 50 through 52. The remaining two columns of the former Census Use 5 field were added to the Names field expanding its record length to 60 and occupying columns 53 through 112. Record Type C in the 1999 TIGER/Line files included, for the first time, the census tract numbers formatted to display as a "name." The census tract name drops the leading and trailing zeros and, where a census tract suffix exists, added the decimal point. For example, census tract 000100 has a name of "1" and census tract 003201 has a name of "32.01." The census tract number associated with the census tract name shared a field on Record Type C with the Voting District Code. As a result, the field name was changed from VTD to VTDTRACT. Data users were advised to use the Entity Type Code to differentiate between the two entities; records with an Entity Type Code of "T" were census tracts and those with an Entity Type Code of "V" were voting districts. The FIPS Code and Name Relations Applicable Year field on Record Type C became the FIPS Code, Name, and/or Attribute Data Applicable Year field with a field name change from FIPSYR to DATAYR. The Census American Indian/Alaska Native Area Code field became the Census American Indian/Alaska Native Area/Hawaiian Home Land Code field. Its field name changed from AIR to AIANHHCE. The Census Urbanized Area Code field became the Census Urban Area/Urban Growth Area Code field with a field name change from UA to UAUGA. For information on Urban Growth Areas refer to Chapter 4. The Legal/Administrative/Statistical Area Description Code became the Legal/Statistical Area Description Code. Its field name changed from LASAD to LSADC. Also changed was the field name PDC which became PLACEDC. Most of the geographic codes on Record Type S in the 1999 TIGER/Line files were changed to reflect 2000 (TENTATIVE) codes rather than current or 1990 geography. The information in fields identified as 2000 (TENTATIVE) were subject to change. The U.S. Census Bureau was using these fields to exchange data with local partners participating in U.S. Census Bureau programs. Data users were advised not use this information as the Census 2000 geographic codes. On Record Type S, the FIPS Consolidated Metropolitan Statistical Area Code, Current field became the FIPS Consolidated Metropolitan Statistical Area/Metropolitan Statistical Area Code, 2000 (TENTATIVE) field. Its field name changed from CMSA to MSACMSA. The FIPS Metropolitan Area Code, Current field became the FIPS Primary Metropolitan Area Code, 2000 (TENTATIVE) field. Its field name has changed from MA to PMSA. The FIPS 55 Code (American Indian/Alaska Native Area), Current field on Record Type S became the FIPS 55 Code (American Indian/Alaska Native Area/Hawaiian Home Land), 2000 (TENTATIVE) field. The field name changed from FAIR to AIANHH. The Census American Indian/Alaska Native Area Code, Current field became the Census Code (American Indian/Alaska Native Area/Hawaiian Home Land), 2000 (TENTATIVE) field. The field name changed from AIR to AIANHHCE. The American Indian Trust Land Flag, Current field became the American Indian/Hawaiian Home Land Indicator, 2000 (TENTATIVE) field. Its field name changed from TRUST to AIHHTLI. The Census Alaska Native Regional Corporation Code field was deleted and replaced by Reserved Space 6. On Record Type S, the U.S. Census Bureau renamed several fields. FCCITY became CONCIT, FMCD became COUSUB, FSMCD was renamed SUBMCD, FPL became PLACE, and CT became TRACT. All these fields where changed to contain 2000 (TENTATIVE) geographic codes. The Census Block Number, 1990 field became the Census Block Number, 2000 field. Its field name changed from BLK to BLOCK. This field was blank in the 1999 TIGER/Line files. The FIPS State Code and FIPS County Code fields were changed to contain 2000 (TENTATIVE) geographic codes. The State Senate District Code and State House District Code fields on Record Type S were changed to State Legislative District Code (Upper Chamber), 2000 (TENTATIVE) and State Legislative District Code (Lower Chamber), 2000 (TENTATIVE) fields. Their field names changed from STSENATE and STHOUSE to SLDU and SLDL. The Voting District Code field, which was blank in earlier versions of the TIGER/Line files, contains 2000 (TENTATIVE) codes. The CENSUS Use 7 field on Record Type S became the Oregon Urban Growth Area, 2000 (TENTATIVE) field with a field name of UGA. Refer to Chapter 4 for more information about Urban Growth Areas. Reserved Space 7 was replaced by Census Block Group, 2000 (TENTATIVE) with a field name of BLKGRP. Three other field names changed. COUNCOL was renamed COUNTYCOL, BLKCOL became BLOCKCOL, and ZCTA became ZCTA5. Address Ranges and ZIP Codes The 1999 TIGER/Line files contained improvements in address range information resulting from Census 2000 preparations. In addition, ZIP Codes were updated in selected areas. Refer to the Address Information Methodology section in Chapter 3 for more information. No single address-address ranges appeared in the 1999 TIGER/Line files, including out-of-parity and out-of- sequence addresses. These addresses were withheld to protect the confidentiality of individual addresses collected through census field operations as specified by Title 13 of the U.S. Code. Refer to the Address Ranges section in Chapter 3 for more information. Beginning with the 1999 TIGER/Line files, there are multiple ZIP+4 Add-On codes associated with a single address range. See the Postal Add-On Code section in Chapter 3 for more information. New Census Feature Class Code (CFCC) Beginning with the 1999 TIGER/Line files, some street features that normally were classified with an "A" class CFCC are coded with a "P" instead of the "A." These are provisional features that have not been verified by census staff but were added to the Census TIGER data base pending Census field staff verification. Refer to the Census Feature Class Codes (CFCCs) section in Chapter 3 for more information. Diacritical Marks in the 1999 TIGER/Line files The U.S. Census Bureau no longer is using codes to represent the diacritical marks. Beginning with the 1999 TIGER/Line files, the U.S. Census Bureau used the ISO 8859-1 character set, commonly referred to as Latin1, to identify characters with diacritical marks. Refer to the Feature Identifiers section in Chapter 3 for more information. Internal Points The U.S. Census Bureau recalculated the internal points for polygons. In previous versions of the TIGER/Line files, some of the internal points fell on or outside the boundary of the polygon rather than within the polygon. Depending on the precision of a particular software or hardware system, this caused some data users to find internal points outside the correct polygon. The recalculation of the polygon internal points resolved many of these problems. However, the internal point for a few very small or irregularly shaped polygons still fall on the boundary of the polygon. 1998 TIGER/Line Files The 1998 TIGER/Line files had the same structure as the 1997 TIGER/Line files; there were no record additions or deletions. However, there were some field name, file name, and content changes including corrections to the data format information appearing in Chapter 6. Field Definition Changes There were two field name changes on Record Type 1. The U.S. Census Bureau renamed the CTBNAL and CTBNAR field names as CTL and CTR. There were several changes to the fields on Record Type 3. Reserved spaces two and three in the 1997 TIGER/Line files were replaced in the 1998 TIGER/Line files by FIPS 55 Code (ANRC), Current Left and FIPS 55 Code (ANRC), Current Right. Reserved spaces four and five were converted to Census Use fields and Reserved Space 6 was renumbered. The U.S. Census Bureau renamed the VTDL and VTDR field names as VTD90L and VTD90R. Two changes occurred on Record Type A. The Reserved Space 1 field was replaced by Census Urbanized Area Code, 2000 with a field name of UA. This field is blank in the 1998 TIGER/Line files. The Census Urbanized Area Code, 1990 field name was changed from UA to UA90. The length of the Name of Geographic Area field on Record Type C was changed from 66 characters to 58 characters and comprised columns 55 through 112. The FIPS Code and Name Relationship Applicable Year field was expanded from two characters to four characters, using columns 11 through 14. As a result, the FIPS 55 Code occupied columns 15 through 19, the FIPS Class Code occupied columns 20 through 21, the Census Place Description Code appeared in column 22, the Legal/Administrative Statistical Area Description Code occupied columns 23 through 24, the Entity Type Code appeared in column 25, the Metropolitan Area Code occupied columns 26 through 29, the School District Code occupied columns 30 through 34, the Census American Indian/Alaska Native Area Code occupied columns 35 through 38, and the Census Voting District Code occupied columns 39 through 44. The Census Urbanized Area Code was expanded from four characters to five characters, using columns 45 through 49. The U.S. Census Bureau added a two-character Census Alaska Native Regional Corporation Code in columns 50 and 51 and the remaining characters freed by the change to the Name of Geographic Area field were replaced with a Census Use 5 field in columns 50 through 52. The U.S. Census Bureau made a number of field name changes on Record Type S for the 1998 TIGER/Line files. The field names CMSAMSA and PMSA were changed to CMSA and MA. The field names STATECU and COUNTYCU were renamed STATE and COUNTY. The BLK00 field name was renamed BLK and VTD00 was renamed VTD. The Census Tract/BNA Code, 2000 field on the 1997 TIGER/Line files became Census Tract Code, 1990 on the 1998 TIGER/Line files with a field name change from CTBNA00 to CT. Reserved Space 10 became Census Use 6. The length of the State Senate District Code and State House District Code fields in Record Type S was changed from six characters to three characters. The six characters freed by this change became Census Use 7 and Reserved Space 7 fields. On Record Type S, reserved spaces 11 through 14 and the filler occupying columns 103 through 120 were restructured. The 1998 TIGER/Line files allocated these columns to FIPS Collection State Code, 2000; FIPS Collection County Code, 2000; Collection Block Number, 2000; Collection Block Number Suffix, 2000; ZIP Code Tabulation Area, 2000; and Reserved Space 8. 1997 TIGER/Line Files The 1997 TIGER/Line files had the same structure as the 1995 TIGER/Line files; there were no record additions or deletions. However, there were some field name, file name, and content changes. Field Definition Changes The U.S. Census Bureau redefined the concept of version. The four-digit version code no longer is a number that represented a fixed version that could be referenced nationwide. The version code became a four-digit number that represented the month and year (mmyy) the file was extracted from the Census TIGER data base. Adjacent counties in a state may have different version codes if they were extracted at different points in time. There were several changes to the fields on Record Type 3. The reserved spaces one through four in the 1995 TIGER/Line files contained four 1990 American Indian and Alaska Native area census code and American Indian trust land flag fields in the 1997 TIGER/Line files. These four fields were: Census American Indian/Alaska Native Area Code, 1990 Left (column positions 58 through 61); Census American Indian/Alaska Native Area Code, 1990 Right (column positions 62 through 65); American Indian Trust Land Flag, 1990 Left (column position 66); and American Indian Trust Land Flag, 1990 Right (column position 67). Deleted from Record Type 3 in the 1997 TIGER/Line files were the Census Alaska Native Regional Corporation Codes, Current Left and Census Alaska Native Regional Corporation Codes, Current Right. As a result of these deletions, reserved space filled columns 86 through 107 of the 1997 TIGER/Line files and the reserved space fields on the record were renumbered and reconfigured. Two changes occurred on Record Type A. The School District Code, Middle School field, in columns 60 through 64 of the 1995 TIGER/Line files was eliminated and replaced with Reserved Space 1 in the 1997 TIGER/Line files. Reserved Space 9 in the 1995 TIGER/Line files (columns 95 through 98) was replaced with the Census American Indian/Alaska Native Area Code, 1990 in the 1997 TIGER/Line files. The length of the Reserved Space 9 field in Record Type A was changed from nine characters to four characters. The five characters freed by this change were used for the 1990 state and county codes and are the source for determining the 1990 census tabulation codes. There were changes to Record Type C in the 1997 TIGER/Line files. The 1995 TIGER/Line files had ten characters in columns 23 through 32 which contained the Census Alaska Native Regional Corporation Code, FIPS Consolidated Metropolitan Statistical Area/Metropolitan Statistical Area Code, and the FIPS Primary Metropolitan Statistical Area Code. The 1997 TIGER/Line files allocated these columns to Entity Type Code, Metropolitan Area Code, and School District Code. We standardized the file suffix names that appear inside the compressed files (tgrxxxxx.zip). This suffix now will consistently be .rtn where n is the record type. In examining the record layouts in Chapter 6, we corrected information concerning the valid existence of blank values and data formats. Change in Naming Standards for Record Type 1 The U.S. Census Bureau changed its naming standards in Record Type 1 affecting the data in the Feature Direction, Prefix (FEDIRP), Feature Name (FENAME), Feature Type (FETYPE), and Feature Direction, Suffix (FEDIRS) fields. In previous TIGER/Line products, directional prefixes and suffixes could appear for any type of line feature. For the TIGER/Line 1997, only road features, those features with a Census Feature Class Code (CFCC) in the A class, should have feature directional data in the directional fields. Other types of chains representing other types of features (for example, hydrologic features in CFCC class H) no longer are standardized to show directional information. The U.S. Census Bureau also modified the extraction of feature directional, name, and type information to improve the standardization of road feature information. The improvement parses a greater number of road chains into the correct feature identifier fields. 1995 TIGER/Line Files No record types were added or deleted between the 1994 and 1995 versions of the TIGER/Line files. However, there were field definition and coordinate datum changes, as well as address information improvements, in the 1995 TIGER/Line files. Field Definition Changes The CENID field was changed from numeric to alphanumeric in the 1995 TIGER/Line files to permit a wider range of entries within the same field length. Boundary and Area Changes With the exception of Hawaii, Record Type 1 no longer contained census designated place (CDP) information. Since CDPs are defined at the time of each decennial census and are valid only for the presentation of decennial census data, the CDP complete chain information was removed from Record Type 1 which contained only current geography, but retained on Record Type 3 which had 1990 geography. Because Hawaii did not have independently defined incorporated place boundaries, it used CDP boundaries as substitutes for these legal boundaries. Thus, its CDP complete chain information was retained on Record Type 1. Coordinates For the 48 contiguous states, the District of Columbia, Alaska, Puerto Rico, and the Virgin Islands, the coordinates in the 1995 TIGER/Line files were in the North American Datum of 1983 (NAD83). In all previous versions, the coordinate datum for the above areas was NAD27. Regional datums were used for Hawaii and the Pacific Island Areas. 1994 TIGER/Line Files The format and structure of the TIGER/Line files changed between the 1992 and the 1994 versions. In the 1994 TIGER/Line files, there were field definition changes and additional record types that accommodated new information or information that was previously supplied separately in other U.S. Census Bureau products. New Record Types The 1994 TIGER/Line files included five new record types-9, C, H, S, and Z. Record Type 9 contained key geographic locations (KGLs). A KGL was a particular type of point landmark with residential or economic significance. Record Type C replaced information that was supplied separately in the TIGER/Geographic Name files. Record Type C provided a unique list of all geographic entities with their code, name, and status. The FIPS Year field had three values, 90 for geographic names and codes valid for the 1990 census, 94 for geographic names and codes valid for the current year, and blank when the geographic names and codes were the same for 1990 and 1994. Multiple records for the same geographic entity showed its change or correction over time. Record Type H described the history of TIGER/Line IDs when complete chains were split or merged. Two fields (HIST and SOURCE) on Record Type H were not yet maintained in the Census TIGER data base and were blank. Record Type S had geographic area codes for polygons. It was similar to Record Type A (which also had geographic area codes for polygons) and was linked to Record Type P. There was a Record Type S for every polygon in Record Type P. Several fields were reserved for use by participants in U.S. Census Bureau programs. The WATER field had two values, 0 for land or 1 for water. The Congressional District codes for the current Congress (in this case, the 103rd) were moved to Record Type S. The current Congressional District code, when combined with the 1990 state codes, created valid geographic areas. When only current state geographic codes were combined, nonexistent geographic areas may have resulted. The fields for the 101st and 103rd Congressional District codes in Record Type A were replaced with those designated for the 106th and 108th. However, these fields were blank in the 1994 TIGER/Line files. Record Type Z linked a Postal +4 Add-On code to an address range in either Record Type 1 or Record Type 6. TLID fields were matched on these records. If the RTSQ field on Record Type 6 contained a 0, the Postal +4 Add-On codes applied to the address ranges in Record Type 1. If the RTSQ field contained a number greater than 0, the Postal +4 Add-On codes applied to the address ranges in the Record Type 6 that had the identical RTSQ value. Deleted Record Types In the 1994 TIGER/Line files, Record Types F and G were deleted because they were no longer used. Record Type F showed geographic codes as of January 1, 1990 that were corrected to resolve questions raised by local officials about the 1990 census data tabulations. Record Type G showed geographic codes (generally as of January 1, 1992) for those situations where geographic entities reported boundary changes during the U.S. Census Bureau's annual survey of governmental units. In the 1994 TIGER/Line files, information previously reported in Record Type G became implicit in the current geographic codes in Record Types 1 and S. Field Definition Changes The geographic area codes on Record Type 1 represented current geography rather than the 1990 census tabulation geography. The census tract and block remained as 1990 geography. In a few Type 1 records, the current state and county, when combined with the 1990 census tract and block, created nonexistent geographic areas. To avoid nonexistent geographic areas, it was important not to mix the 1990 geographic codes with the current geographic codes. The 1990 state, county, place, census tract, and census block codes all were found on Record Type 3. Record Type 3 no longer identified 1980 geographic area codes or contained census codes for places, minor civil divisions, and sub-minor civil divisions. These fields were replaced with the 1990 geographic areas that previously appeared in Record Type 1. Current geographic areas included on Record Type 3 were the Alaska Native Regional Corporations and the American Indian/Alaska Native Areas (AIANAs). Census Alaska Native Regional Corporation codes were eliminated from Record Type 1 and replaced by four fields. Two fields were reserved for census use. Two fields carried American Indian Trust Land Flags and contained two values, an "I" for individual trust land or a "T" for tribal trust land. The trust land flag more accurately portrayed the American Indian areas. Record Type 7 excluded key geographic locations (KGLs). These appeared in the new Record Type 9. Coordinates In the 1994 TIGER/Line files, NAD27 was the coordinate datum used for the 48 contiguous states, the District of Columbia, Alaska, Puerto Rico, and the Virgin Islands. Regional datums were used for Hawaii and the Pacific Island Areas. The accuracy of the feature coordinates in Alaska was improved by shifting them in relation to a sample of points of known higher accuracy.