The data set consisted of incident breast cancer cases in women aged 20 years and older from January 1994 to December 2003 in the Puget Sound area. The data set was obtained from the SEER cancer registry. The stage of cancer was also provided (in situ (Stage I), localized (Stage II), regional (Stage III) and distant (Stage IV)). Information is available for thirteen counties: Clallam, Grays Harbor, Island, Jefferson, King, Kitsap, Mason, Pierce, San Juan, Skagit, Snohomish, Thurston and Whatcom. In addition, the patient age at diagnosis (20-49, 50-69, 70+) and patient race (White, Black, American Indian, Aleutian, Alaskan Native or Eskimo, Asian Descent or Hawaiian and unknown/other) was also provided. Population specific data was obtained from the United States 2000 census (http://www.census.gov). The population data provided was the population count for each count for each race and age group.