Looking for a loan? Trying to get credit? Better know your credit score.

According to a nationwide survey conducted by Ad Council and Opinion Research USA, 70 percent of Americans think their credit score is good, but half don't know the score.

Sixty seven percent mistakenly think their credit score is affected by employment.

In this tightening credit market, not taking action to improve your credit score can spell disaster for consumers trying to get credit or take out a loan. Financial institutions are getting tough and looking for even higher credit scores than before.

So the Ad Council is launching a new campaign to set the record straight about how credit scores are calculated and what can bring your credit score down.

The campaign is co-sponsored by the Consumer Bankers Foundation and the Leadership Conference on Civil Rights Education Fund.

The groups have established a new Web site that offers two quizzes to test your credit score I.Q.

The site also tells you how to obtain your credit scores from the different credit bureaus, and what to do to get the numbers up.

The biggest things that can lower your credit score are late payments, too much new credit, too many inquiries, and credit card balances that exceed more than 50 percent of your limit.