U. S. BUREAU OF THE CENSUS 1980-90 COMPONENTS OF CHANGE FILE DOCUMENTATION Summary: The 1980-90 Components of Change file for states and counties contains national, state, and county census counts for 1980 and 1990, 1980-90 cumulative components of change; and annual births and deaths by estimation period in the 1980s. Data: 1. National, state and county FIPS codes and names. For the nation, state FIPS code = 00, county FIPS code = 000, and the name is the United States. On the state line the FIPS county code = 000. Show area names on each line. The area name for a county with a FIPS code of "000" is the name of the state in which that county is located. 2. 1980 census counts of total population updated to reflect December 31, 1989 geography and all errata processed to that point 3. 1990 census counts of total population as enumerated (no errata and no geographic updates). 4. 1980-90 change (1990 census count - 1980 census count), and percent change. Percent is rounded to one place after the decimal and the decimal is shown. 5. Cumulative statistics for April 1, 1980 through March 30, 1990. Summary statistics for the decade are created using data already rounded to the nearest integer. 6. Residual change for 1980-90 and percent residual change. Residual change is a combination of net migration over the decade between states and counties, differential census coverage error, and coverage error in reporting vital events. The census coverage error is considered to be of a different magnitude in the 1990 census than it was in the 1980 census. Residual change is calculated as follows: where RC8090 = residual change C90 = 1990 census count C80 = 1980 census count Bcum = 1980-90 births Dcum = 1980-90 deaths 7. Births and deaths by estimation period. The estimation periods are: April 1, 1980 through June 30, 1981 July 1, 1981 through June 30, 1982 . . . July 1, 1988 through June 30, 1989 July 1, 1989 through March 30, 1990 These births and deaths are based on calendar year vital statistics data collected from the 50 states and the District of Columbia through the Federal-State Cooperative Program for Population Estimates, as reviewed and edited through May 1992 by Population Division, Population Estimates Branch staff. Significant revisions have been made in selected counties and selected years in the review. These data thus are not consistent with the data used to produce state and county population estimates in the 1980s. Fractional portions of years are based on the number of months involved. For the 3-month portion of 1990, 0.25 of 1989 vital statistics were substituted. Summary statistics for national and state data are the summation of county-level data previously rounded to integers. These national numbers thus do not necessarily match with the vital statistics used in developing national population estimates (The national-level vital statistics are obtained from the U.S. Department of Health and Human Services, National Center for Health Statistics). Geography: Data are shown for the United States, all states (including the District of Columbia), all counties and county equivalents in the United States (including census areas in Alaska, parishes in Louisiana, the District of Columbia, and independent cities in Maryland, Missouri, Nevada, and Virginia). Separate data are shown for Kalawao County, HI; rather than being included with Maui County (as was the custom in the past). The series includes data for two counties in Arizona and New Mexico and three Alaska boroughs established since 1980: 1. La Paz County, AZ (separated from Yuma County in 1983) 2. Cibola County, NM (separated from Valencia County in 1981) 3. Northwest Arctic Borough, AK (generally coextensive with the former Kobuk Census Area and created in 1985) 4. Aleutians East Borough, AK (separated from the former Aleutian Islands Census Area in 1987; the remainder is now known as Aleutians West Census Area) 5. Lake and Peninsula Borough, AK (separated from Dillingham Census Area in 1989) The 1980 census counts reflect errata and boundary changes as processed through December 31, 1989. The vital statistics data reflect boundary changes occurring in the 1980s. Record Layout: The record layout is attached. Additional Information: For additional information concerning the files, contact Population Division, Statistical Information Staff, Bureau of the Census, Washington, D.C. 20233, Phone: (301) 457-2422. For additional information concerning the technical documentation, contact Population Division, Population Estimates Branch, Bureau of the Census, Washington, D.C. 20233, Phone: (301) 457-2380. Attachment 1980-90 COMPONENTS OF CHANGE FILE RECORD LAYOUT File Name: COFC8090.POP File Type: ASCII Flat File Record Count: 6386 Character Item Description 1 Record Type = 'A' or 'B' 2 Blank 3-4 FIPS State Code ('00' = United States) 5-7 FIPS County Code ('000' = U.S. or State total) 'A' Records: 8-17 April 1, 1980 Corrected Population Count 18-27 April 1, 1990 Population Count 28-37 Numeric Change, 1980-1990 38-47 Percent Change, 1980-1990 (1 expressed decimal) 48-57 Cumulative Births, 1980-1990 58-67 Cumulative Deaths, 1980-1990 68-77 Residual Change, 1980-1990 78-87 Percent Residual Change, 1980-1990 (1 expressed decimal) 88 Blank 89-90 State Postal Abbreviation ('US' = United States) 91 Blank 92-135 Area Name 136-167 Blank 'B' Records: 8-15 1980-81 Births 16-23 1981-82 Births 23-31 1982-83 Births 32-39 1983-84 Births 40-47 1984-85 Births 48-55 1985-86 Births 56-63 1986-87 Births 64-71 1987-88 Births 72-79 1988-89 Births 80-87 1989-90 Births 88-95 1980-81 Deaths 96-103 1981-82 Deaths 104-111 1982-83 Deaths 112-119 1983-84 Deaths 120-127 1984-85 Deaths 128-135 1985-86 Deaths 136-143 1986-87 Deaths 144-151 1987-88 Deaths 152-159 1988-89 Deaths 160-167 1989-90 Deaths