One of the biggest and oldest surveys in America will hit mailboxes this week, and its results will inform countless decisions, from how federal funds are divvied up to how advertisers analyze their target audiences.

It’s available in six languages, and anyone who doesn’t participate may be slapped with a fine, per federal law.

Say hello to Census 2010.

Every 10 years, the government sends out its questionnaire to track US population and determine how to apportion seats in the House of Representatives.

This year, the government lined up a savvy $130 million campaign – complete with Super Bowl and Winter Olympics ads, a census-sponsored NASCAR race car, and a nationwide road tour – to encourage people to mail back their census forms. If every household mails back its form (more than 120 million have been mailed out), the government could save $1.5 billion in follow-up visits.

To save the government – and yourself – some dough, read on for more tips and trivia about the 2010 Census.

• 10 questions in 10 minutes. One of the shortest census questionnaires in history, the 2010 Census has only 10 questions, which should take 10 minutes to fill out, according to the Census Bureau. Among the questions asked: whether a resident owns or rents, as well as information about each household member, including name, sex, age, race, and relationship to the person filling out the form.

• To include or not to include? The census asks how many people live or sleep in a given household as of April 1. Respondents should include babies born on or before April 1, 2010, as well as non-US citizens. College students who live away from home and military personnel should not be counted on household surveys. Divorced parents who share custody of a child should indicate where a child usually lives. Residents who need help filling out the form can do so at a questionnaire assistance center. Locations are available online.

• $400 billion and 435 seats in the US House of Representative. Census data determine how more than $400 billion in federal money is distributed, for everything from roads and schools to healthcare and child-care centers. It also determines how many lawmakers each state will have in the US House of Representatives.

• It’s in the Constitution. Article I, Section 2, to be exact. It specifies that congressional seats will be distributed proportionately among states on the basis of a census to be conducted every 10 years. Federal law penalizes those who don’t fill out a form ($100 fine) or who provide false information ($500 fine).

• Americans have been counted since 1790. The 2010 Census is the 23rd head count in US history. The first was conducted on Monday, Aug. 2, 1790. Population? 3.9 million. This year’s official Census Day is April 1. Expected population? 309 million.

• Who’s filling it out – and who isn’t. The Census Bureau predicts that two-thirds of US households will fill out and mail back the 2010 Census. Among those least likely to return forms are illegal immigrants, Hispanics, young adults, city dwellers, and residents displaced by foreclosures. Homeless people may not be left out, however: Census takers will canvass city streets in an attempt to include them.

• Which states get the most federal dollars? Rural areas and places with a large poor population tend to benefit most from an accurate census because the largest state program that relies on federal census statistics is Medicaid, the government healthcare program for low-income individuals. According to an analysis by the Brookings Institution, the places that received the most census-based federal dollars per capita were the District of Columbia, Vermont, Alaska, New York, and Massachusetts.

• Which states might get cheated? In 2000, Florida, Georgia, Nevada, Arizona, Texas, and North Carolina each had below-average mail participation rates. Since then, they’ve also seen higher rates of foreclosures and rapid growth of Hispanics and blacks – groups that are less likely to return their forms. If responses are low this year, these states could be cheated of federal dollars and congressional seats. If not, they stand to gain at least one House seat each.

• Census 2010 by the numbers: 360 million, 29 miles, 11.6 million pounds. That is the total number of questionnaires printed (360 million), how high they would stand stacked in a pile (29 miles high – more than five times higher than Mt. Everest), and the collective weight of the paper that the questionnaires were printed on (11.6 million pounds). If stretched end to end, the questionnaires would circle the globe three times.

• $0.42 versus $56. This is how much it costs the government if residents mail back their census form (42 cents each), compared with the estimated cost of obtaining a household’s census response in person if a household fails to mail back the form.