Two weeks to answer 10 questions – that’s the task given residents of the United States via large white envelopes with questionnaires that landed in mailboxes yesterday.

The U.S. Census is tallying up all the people living within the country’s borders for a variety of reasons. Not only does the once-a-decade count help allocate appropriate representation in Washington, but also allows for adequate distribution of resources and services.

The census forms ask only 10 questions and the information collected remains confidential. It is not sold or shared with commercial interests and no one has access to the data once the forms are returned. People who don’t turn in their forms can expect a visit from a representative of the Census Bureau to get the information.

The Census Bureau today estimated that if every household completed and mailed back their census form, taxpayers could reduce the cost of taking the census by $1.5 billion. The Census Bureau saves about $85 million in operational costs for every percentage point increase in the nation’s participation rate by mail.

“Here is something every family can do to help their government save money, and get an accurate Census at the same time. Mailing back your census form when it arrives will contribute to saving hundreds of millions of taxpayer dollars,” said Census Bureau Director Robert M. Groves. “It’s a lot less expensive to get responses back by mail than it is to send census takers to knock on doors of households that failed to respond.”

“It costs the government just 42 cents for a postage paid envelope when a household mails back the form,” said Groves. “It costs $57 to send a census taker door-to-door to follow up with each household that fails to respond.”

Even with these changes to make the census the shortest and easiest in a lifetime, the Census Bureau still projects that it will have to send census takers to an estimated 48 million households that do not respond by mail. Following up door-to-door to count households from May to July will require hiring about 650,000 census workers.

Here are the questions and some of the reasoning behind the government asking them:

How many people were living or staying in this house, apartment or mobile home on April 1, 2010? Every 10 years, April Fool’s Day takes on a serious tone and becomes Census Day. This question establishes the number of people at the given residence.

Were there any additional people staying here April 1, 2010 that you did not include in Question 1? This question has been part of the government’s query since 1880. Just in case someone is left out of Question 1, this is the place to put them.

Is this house, apartment or mobile home: owned with mortgage, owned without mortgage, rented, occupied without rent? Again, one of the questions for the last 120 years. Homeownership rates serve as an indicator of the nation’s economy; it’s also used to administer housing programs and inform planning decisions.

What is your telephone number? This is used just in case forms are returned incomplete or missing information.

Please provide information for each person living here. Start with a person here who owns or rents this house, apartment, or mobile home. If the owner or renter lives somewhere else, start with any adult living here. This will be Person 1. What is Person 1’s name? Listing the name of each person in the household assures that everyone is counted in large households. Names are needed if additional information about an individual must be obtained to complete the census form. Federal law protects the confidentiality of personal information, including names.

What is Person 1’s sex? Asked since 1790. Many federal programs differentiate between males and females for funding, implementing and evaluating their programs. Also, sociologists, economists and other researchers who analyze social and economic trends use the data.

What is Person 1’s age and date of birth? Asked since 1880. Federal, state and local governments need data about age to interpret most social and economic characteristics, such as forecasting the number of people eligible for Social Security or Medicare benefits. This data is also used to plan and evaluate government programs and policies that provide funds or services for children, working-age adults, women of childbearing age or the older population.

Is Person 1 of Hispanic, Latino or Spanish origin? This is one of the newer questions on the Census, added in 1970. The data collected in this question is needed by federal agencies to monitor compliance with anti-discrimination provisions, such as those of the Voting Rights Act and the Civil Rights Act. State and local governments may also use the data to help plan and administer bilingual programs for people of Hispanic origin.

What is Person 1’s Race? Asked since 1790. Along with assuring compliance with the above-mentioned federal programs, race data is also used to ensure fairness of employment practices, to monitor racial disparities in health and education programs and to plan and obtain funds for public services.

Does Person 1 sometimes live or stay somewhere else? This is asked to ensure response accuracy and completeness.

For more information on the 2010 Census, go to their website.