The current door-to-door phase of the 2010 Census is about 94 percent complete, but there are several reasons why a census worker may visit your home in coming weeks.

Robert Groves, director of the U.S. Census Bureau, announced this week that about 44 million census forms had been completed and checked-in as of Sunday, leaving about 3 million forms to be collected and processed.

"We are somewhat ahead of schedule and certainly under budget," Groves said.

Since May 1, about 550,000 census employees have been going door-to-door nationwide to obtain completed census questionnaires from more than 47 million households that failed to return a form by April 16.

"In some parts of North Carolina, the workload was completed weeks ahead of the July 10 deadline for the Nonresponse Followup phase," said William W. Hatcher, Charlotte regional director for the Census Bureau.

Nevertheless, he added, over the next several weeks census workers will continue to contact some households in North Carolina as part of one of several quality-control operations. They include:

n Coverage follow-up: Until mid-August, households will be called to clarify answers provided on the census questionnaire (for example, the number of people listed at an address doesn't match the number of names provided).

n Vacant delete check: In July, census workers will double check vacant households and those deleted as nonexistent on April 1, the reference date for the 2010 census. They will visit housing units from which the bureau received blank or incomplete forms.

n Field verification: During August, census workers will visit households for which a form has been received but whose address does not match an address in the master file. This operation also seeks to resolve suspected duplicate addresses within the same block.

"These operations are supplemented by other quality-assurance processes to maximize accuracy," Hatcher said. "In some cases, that means a home may be visited more than once."

Some households that mailed in a form have received a visit from a census worker. Reasons include incomplete or conflicting answers or forms received after deadline.

"If you are one of the small percent of North Carolina homes that are visited, please take a few minutes to speak with the census taker," Hatcher said. "Our mission is to count everyone, once and in the right place. We check and double check to make sure we get it right."

Nationwide, 72 percent of U.S. households mailed back the form on time. The mail participation rate for North Carolina was 74 percent.

The 2010 census is the official count of everyone living in the United States and is required by the Constitution. Census data are used to allocate congressional seats to the states and to distribute more than $400 billion in federal funds to tribal, state and local governments each year. State-by-state results must be reported to the president by December 31.

Census takers will have an official identification badge, and many will also carry a black bag marked with the words "U.S. Census Bureau."

Census takers will never ask to come into your home, or ask for bank, credit card or Social Security numbers.