As NCI continues to evaluate the comparability of race data between cancer incidence and U.S. Census Bureau's population estimates and to explore reporting options, cancer incidence and mortality rate statistics released in April 2026 will continue to use bridged race categories.

The county bridged race population estimates currently used in the SEER*Stat software to calculate cancer incidence and mortality rates are available for download (see Download U.S. Population Data). These estimates reflect NCI modifications to the intercensal and postcensal Vintage 2024 annual time series of July 1 county population estimates by single year of age, sex, bridged race, and Hispanic origin.

2010-2019 Intercensal Estimates

Intercensal estimates used by NCI as denominators are typically produced by U.S. Census Bureau's Population Estimates Program about two years after each decennial census. Previous intercensal estimates (i.e. estimates for 1980-2009) were produced by Census Bureau. Because Census Bureau’s 2010-2019 intercensal estimates were not available, starting with the April 2024 release, NCI began using estimates produced by Woods & Poole Economics, Inc. (W&P) under contract with NCI. In the April 2026 release, W&P updated the estimates to incorporate the revised April 2020 "blended base (PDF)" used in Vintage 2024, applying methods aligned with Census Bureau methodologies. Although the Census Bureau published the intercensal estimates in 2025, they are based on a different 2020 anchor population than Vintage 2024, therefore may introduce artifactual changes in trends when used together as denominators. Detailed methodology is described in W&P's technical report (PDF, 698 KB).

Postcensal Vintage 2024 Estimates

Vintage 2024 population estimates are produced by the U.S. Census Bureau through an Interagency Agreement with NCI. Census Bureau revises vintage populations every year to incorporate most up-to-date input data and methodological improvements. Compared to Vintage 2023, revisions in Vintage 2024 are generally small but may affect cancer statistics; notably, the populations aged 90+ in 2023 were revised upward by approximately 1-2.5% across all race/ethnic groups. This upward revision appears to reflect population aging, with shifts from ages 70-84 into ages 85+, as well as overall upward revision of about 0.5% in the total U.S. population. These adjustments are similar in magnitude to those between Vintage 2023 and Vintage 2022. For additional details on revisions in the prior vintage, please see Impact of Revisions on 2020 U.S. Population Estimates from Vintage 2023.

In addition, starting with Vintage 2022, nine planning regions are used as county-equivalent geographic units for reporting July 1 population estimates series for the state of Connecticut. To align with the geographic unit currently used for tracking cancer incidence and deaths, W&P converted 2020-2024 populations for Connecticut from planning regions to counties.

Modifications

Modifications made by NCI to W&P and Census Bureau estimates are documented in Modifications to the County Population Data and are summarized below.

  • The population estimates incorporate intercensal (for July 1, 2000-2009, July 1, 2010-2019) and Vintage 2024 (for July 1, 2020-2024) bridged race estimates that are derived from the original multiple race categories in the 2000, 2010 and 2020 Censuses. The bridged race estimates and a description of the methodology used to develop them appear on the National Center for Health Statistics website.
  • A modification that NCI has made to the Census Bureau estimates only affects population estimates for the state of Hawaii. Based on concerns that the native Hawaiian population has been vastly undercounted in previous censuses, the Epidemiology Program of the Hawaii Cancer Research CenterExternal Web Site Policy has recommended an adjustment to the populations for their state. The "Hawaii-adjustment" to the Census Bureau’s estimates has the net result of reducing the estimated white population and increasing the estimated Asian and Pacific Islander population for the state. The estimates for the total population, black population, and American Indian and Alaska Native populations in Hawaii are not modified.
  • Population estimates for 2005 are adjusted for population shifts due to hurricanes Katrina (August 29) and Rita (September 24). These estimates are lower for counties/parishes that had direct hurricane impact and higher for counties/parishes that were destinations for those displaced. See Adjusted Populations for the Counties/Parishes Affected by Hurricane Katrina and Rita for more information.

A further modification made by W&P to all intercensal and postcensal estimates (from July 1, 1969 to July 1, 2024) breaks age data for 85+ into single year of age up to 89 and 90+, for all combinations by county, sex, bridged race and Hispanic origin. The age data is used to calculate cancer rates adjusted using 20 age groups (with the additional 85-89 age group) in NCI's April 2026 release. This switch from 19 age groups to 20 age groups for age adjustment will result in different rates even in years where the numerators (case counts for incidence rates and death counts for mortality rates) remain unchanged, reflecting differential weights given to 84-89 age group and 90+ age group populations.

Single year of age population estimates by county are available on the Download U.S. Population Data page. The methods used to create these estimates are described in Single Year of Age County Population Estimates.

Standard Population Data Files containing age distributions used as weights to create age-adjusted statistics are also available.

Suggested Reference for Intercensal 2010-2019 Population Estimates: 2010 to 2019 Intercensal Estimates of County Population by Age, Sex, and Bridged Race for Vintage 2024 Postcensal Estimates, Woods & Poole Economics, Inc., Washington D.C. January 2026.

Note: The 1969-2023 U.S. Population Data will be available through May 2026.