Single Year of Age County Population Estimates, 1969-2005
Release date: March 3, 2008

2000-2005

A set of July 1, 2000-2005 bridged single-race population estimates were obtained by NCI from the Census Bureau through an interagency agreement. This file contains populations by year, county, race, Hispanic origin, sex and age. The race groups included in the Census estimates are White, Black, American Indian/Eskimo/Aleut and Asian/Pacific Islander. The age groups consisted of the following 86 categories: <1, 1, 2, 3, …84, and 85+ years. The following steps were taken to create 2000-2005 single year of age estimates:

  • One record was create by year, county, race, Hispanic origin and sex with variables for each of the age-specific populations.
  • Census Federal Information Processing Standards (FIPS) county codes were collapsed to match the county list used by the NCI (See Appendix 1 of methods documentation).
  • Adjustments to the Census Bureau's populations for the state of Hawaii were made using the 2000 Census SF1 file. The proportion of the White Alone population estimate to the total (all racial/ethnic groups combined) population was calculated from the SF1 data for 2000-2005 by year, county, sex, and age. The proportion was applied to the total (all racial/ethnic groups combined) population estimate from the Census Bureau to produce the Hawaii-adjusted White population. Additional racial/ethnic populations for Hawaii were developed in the following manner:
    • Hispanic White = Hawaii-adjusted White X (Census Hispanic White/Census White)
    • Non-Hispanic White = Hawaii-adjusted White - New Hispanic White
    • Hispanic Nonwhite= (Census Total - Hawaii-adjusted White) X (Census Hispanic Nonwhite/Census Nonwhite)
    • Non-Hispanic Asian/Pacific Islander = Hawaii-adjusted Hispanic Nonwhite - (Census Non-Hispanic Black + Census Non-Hispanic American Indian/Eskimo/ Aleut)
    • Hispanic Asian/Pacific Islander = Census Total - (Hawaii-adjusted White + Census Black + Census American Indian/Eskimo/Aleut + Hawaii-adjusted Non-Hispanic Asian Pacific Islander)
  • The adjusted Hawaii data were merged with the other county level data.
  • One record was created by year, county, race, Hispanic origin, sex and age.
  • Race/Hispanic origin populations were summed to create races White, Black and Other.

The 2000-2005 estimates received from the Census Bureau included population estimates for Broomfield county in Colorado, which was created in November, 2001 from parts of Adams, Boulder, Jefferson, and Weld counties. To be consistent with the way numerator data are reported (i.e., mortality and incidence) in 2000 and 2001, however, we derived estimates for the original four Colorado counties (Adams, Boulder, Jefferson and Weld) that existed prior to the creation of Broomfield county. An earlier series of Census Bureau estimates that did not include Broomfield county were used to derive the 2000 and 2001 estimates. The following steps were taken:

  • One record was created from the 2000-2005 data for 2000 and 2001 by year, race, Hispanic origin, age and sex with variables containing the total population for Adams, Boulder, Broomfield, Jefferson, and Weld counties.
  • One record was created from the older 2000-2001 data by race, Hispanic origin, age and sex with variables containing the populations for the individual and sum of the counties for Adams, Boulder, Jefferson and Weld counties. Proportions were calculated for each of the 4 counties to the total of the 4 counties by race, Hispanic origin, age and sex.
  • The proportions calculated above for each of the 4 counties were applied to the current total population estimates for the 5 counties in 2000-2001.
  • One record was created by year, county, race, Hispanic origin, sex and age.
  • The population estimates received from Census for the 5 counties were replaced by the 4 county derived estimates.

Two sets of population estimates are available for 2005: the standard set based on July 1 populations and a set that has been adjusted for the population shifts due to hurricanes Katrina (August 29) and Rita (September 24). For 62 counties and parishes in Alabama, Mississippi, Louisiana, and Texas, the Census Bureau has provided total population estimates for January 1, 2006 (see Special Processing Procedures for the Areas Affected by Hurricanes Katrina and Rita) and estimates by age, sex, and race category for July 1 2006 (see Special Population Estimates for Impacted Counties in the Gulf Coast Area). These data sets were used to develop time-weighted average populations for the 62 counties/parishes in 2005. These estimates are lower than the July 1, 2005 values for counties/parishes that had direct hurricane impact and higher for counties/parishes that were destinations for the people displaced by the hurricanes. The following steps were used:

  • For each to the 62 affected counties and parishes, a daily population estimate was created. For the days prior to the hurricane landfall (August 29 for Katrina and September 24 for Rita), a linear model was used based on the July 1, 2004 and July 1, 2005 population estimates.
  • For the days after the hurricane, we developed an estimate of the January 1, 2006 population by age, sex, and race category. This estimate was generated by applying a county/parish-wide adjustment based on the January 1, 2006 population estimates to the detailed July 1, 2006 population estimates by age, sex, and race category.
  • For the overall 2005 population, we summed the daily estimates and divided by the number of days.
  • For population denominators with cancer data, it is usually assumed that the address at diagnosis is the individual’s permanent address. By using the January 1, 2006 population estimates for all of the post-hurricane period, we assume that the current address was used for people who could not return home by January 1, 2006.
  • Since these adjustments were made for just 62 counties, the resulting total US population is lower than the July 1 total US population. The difference represents people displaced by the hurricanes who went to other parts of the US. A separate dummy state has been introduced that represents these people. It is labeled ” Hurricane Katrina/Rita Evacuees - Populations Only - 2005” and is included by default in rate calculations over the total US. 

1990-1999

The single year of age populations estimates for 1990-1999 were created using bridged-race intercensal population estimates by year, county, single-year of age, Hispanic origin and sex available from the National Center for Health Statistics (NCHS) Web site. The NCI county level populations used in SEER*Stat were used to adjust the Hawaii estimates. The following steps were taken to create the single year of age estimates:

  • The NCHS populations for selected counties were combined to be consistent with the county codes used by the NCI (See Appendix 1 of methods documentation).
  • The NCHS population data contained several cells with negative counts, likely due to incomplete application of the raking techniques used to control more detailed population estimates to marginal totals. We adjusted the NCHS populations to remove negative counts in the following manner. The population for the age with the negative count was set to zero and the age with the highest population in the five year age group was decreased by one. This was done so that the sum of the individual ages in a five year age group stayed the same.
  • For Hawaii, the proportion for each single year of age to the age group total was calculated for each of the age groups (1-4,5-9,10-14,…,80-84) in the NCI estimates by year, race (White, Black, American Indian/Eskimo/Aleut, Asian/Pacific Islander), Ethnicity (Hispanic, Non-Hispanic) and sex.
  • Using the NCI 1990-1999 Hawaii-adjusted population estimates, the proportions from the NCHS data were applied to each age group by year, race, ethnicity and sex.
  • The adjusted Hawaii data were merged with the other county level data.
  • One record was created by year, county, race, Hispanic origin, sex and age group.
  • Race/Hispanic origin populations were summed to create races White, Black and Other.

1969-1989

The single year of age county population estimates for 1969-1989 were created from the 19 age group county population estimates used in the NCI SEER*Stat software. The SEER*Stat populations are available for download (see US Population Data) and the methods used to create them are described in documentation also available in Population Estimates Used in NCI's SEER*Stat Software. Single year of age population estimates provided by a private vendor (Woods and Poole Economics, Inc., 2001 Regional Database, Copyright January 2001) were used to create the NCI single year of age estimates in the following manner:

  • The Woods and Poole single year of age populations for one to eighty four year olds were used by year (1970-1989), state/county, race (White, Black, Other) and sex (male, female). To be consistent with the county codes used by the NCI (See Appendix 1 of methods documentation), various counties available in the Woods and Poole data needed to be combined or recoded (See Appendix 2 of methods documentation). There were also several counties, mainly in Virginia, that are not combined in the NCI data that are combined in the Woods and Poole data. For the purposes of developing the NCI single year of age populations, the information for the combined counties in the Woods & Poole data was used for each of the individual NCI counties (See Appendix 3 of methods documentation).
  • Using the Woods & Poole data, a proportion was calculated for each single year of age to age group total for the following age groups (1-4,5-9,10-14,…,80-84) by year, state/county, race (White, Black, Other) and sex.
  • Using the NCI 1969-1989 population estimates, the proportions calculated from the Woods and Poole data were applied to each age group by year, state/county, race (White, Black, Other) and sex. The proportions for 1970 were used for 1969.
  • For age groups where the Woods & Poole data had zero population and the NCI estimate was greater than zero, the population was distributed equally among the single year ages within the age group.
  • The sum of the new single year of age populations were compared to the original NCI SEER*Stat age group populations by year, state/county, race (White, Black, Other) and sex. Due to rounding, it was necessary to adjust some of the single year of age populations so that their sum matched the original combined age group estimates.