To cite the U.S. Census Bureau in an American Psychological Association-style paper, remember that any report produced by this agency is a government document. Per APA style, list the Census Bureau and report number when creating the citation.
References List Citation
In your references section, list the U.S. Census Bureau as the author of the source, followed by the date the source was published in parentheses -- including the month and day of publication if available. List the title of the report in italics, the report number in parentheses, if available, the location of the source's publisher followed by a colon and the name of the publisher. Each item in your citation should be followed by a period, as follows:
U.S. Census Bureau. (2015, April 8). Recent population trends for the U.S. island areas: 2000 to 2010 (Report No. P23-213). Washington, DC: U.S. Government Printing Office.
Source Taken From the Web
If the report is taken from a website, include the URL of the website in place of the publisher's information. "Retrieved from" precedes the URL in the citation, as follows.
U.S. Census Bureau. (2015, March 19). Desire to Move and Residential Mobility: 2010-2011 (Report No. P70-140). Retrieved from http://www.census.gov/library/publications/2015/demo/p70-140.html
If you quote or cite the Census Bureau in body of the paper, place an in-text citation after the reference. The citation should include the name of the bureau and the year of the source -- though not the month or day, for example: (U.S. Census Bureau, 2015). If the report you cite is paginated, include the page number for direct quotes, as follows: (U.S. Census Bureau, 2015, p.9).