The U.S. Census Bureau is asking state, local and tribal governments for help in compiling updated addresses for their communities as part of an early effort to make the 2010 Census as accurate as possible.

The Census Bureau has a constitutional mandate to count everyone living in the United States, including Puerto Rico, and a complete address list is needed for an accurate count, said Preston Jay Waite, the agency's deputy director and associate director for the decennial census.

"Developing an accurate and up-to-date Master Address File is the first and most vital stage of the decennial census process, ensuring that people residing at the addresses listed in the file will receive a census questionnaire in 2010," Waite said.

The information contained in address lists are confidential by law. The Census Bureau will use the updated address list to deliver the census questionnaires to more than 310 million people living in an estimated 130 million households across the country. The 2010 Census will take most households about 10 minutes to complete, the agency said.

Data from the decennial census directly affects more than $200 billion in federal grant funding.

The census is also used for apportionment. Utah unsuccessfully challenged its narrow miss of a fourth Congressional seat in 2000 and is expected to earn that seat in 2010.