By Steve Bucci, Bankrate.com

Dear Debt Adviser,
I have been monitoring my credit reports for two months online. Recently, I noticed one of my report scores lowered and I'm not sure why. I haven't changed anything in my spending habits or been late in paying anything, so why would only one credit agency change my score?
-- Tracy

Dear Tracy,
I receive quite a bit of mail from readers with average and above-average credit scores wanting to know why their scores dip or whether making some particular financial move will negatively affect their scores. This reminds me of my current and as-yet-unsuccessful attempt to lose 10 pounds. I am dieting and weigh myself every day. You know, some days I eat next to nothing, but the weight still goes up!

What gets lost in both cases is the bigger picture. There are more forces at work here and they work on different timetables. While you aren't looking, companies are providing new data to the bureaus on differing schedules. Some report to one bureau and not others; or an error can show up on one file and not the other. A better way to approach the mystery of the fluctuating score is to ask, on average, every three months in the case of a credit report or each week in the case of the diet, are you doing well based on your situation?

In general, a 40-point difference in a credit score one way or the other is not going to make a big difference in someone's life with an average or above-average score. You obviously want the highest score possible when it matters, such as when applying for a mortgage loan. However, for most of life's financial moves, i.e., paying off a balance or applying for a new credit card or other routine action, a small fluctuation in your score is not going to change your life substantially.

For example, if a potential employer views your credit report to establish your character or for any number of other reasons, the difference between a score of 660 and 700 is not likely to affect how your character is evaluated.

Of the many things that are calculated to come up with your credit score, the two that are weighted the heaviest are: making payments on time (35 percent weighting) and how much you owe (30 percent).

Here are some actions that may affect your score more than you would like:

• Closing an account that changes your credit-owed to credit-limit ratio to higher than 25 percent.
• Removal of an installment account such as car loan or mortgage.
• Closing the credit account that you have had open the longest.
• Late payments.
• Any accounts that are in dispute.
• An increased number of inquiries on your report.
  

To help put your mind, and many other readers' minds, at ease, my advice is to make payments on time and review your overall credit picture three to six months before making any major moves. For the less obsessive of you, there is an excellent credit score estimator that is free, simple and easy to use on the Bankrate.com site.

For all of you, I recommend that you check your credit report at least once a year for accuracy, dispute any incorrect information and then be confident that your score will be an accurate reflection of your credit history at the time it is needed.

Good luck!

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