According to the 2000 Census, San Joaquin County, California has a population of 563,598 people. Of those, 327,607 (58%) are White, 37,689 (7%) are Black, and 172,073 (31%) are Latino. However, 7,146 (or 1% of the 563,598 people) are not residents by choice but are people in prison.
Even though prisoners cannot participate in the local community, the Census Bureau nevertheless counts them as residents of the county where they are incarcerated.
A more accurate description would not include the prisoners. This would give San Joaquin County a population of 556,452 with a demographic that is 58% White, 6% Black, and 31% Latino.
The numbers for Whites, Blacks and Latinos may not add up to the total number because we have not included racial groups other than Whites and Blacks and because the Census Bureau considers "Latino" to be an ethnicity, not a race. Most of the people reported as being Latino are also counted as being White or Black.