Do you ever wonder about all the factors that go into how much you pay for car insurance?

The answer isn't as simple as it might seem. There are dozens of factors that go into how much drivers pay for auto insurance.

"Auto insurance used to be so easy," said Ken Henry, owner of Henry Insurance Agency in Cincinnati. "All you needed to know was someone's age, accidents or tickets and city or county. If your neighbor had the same car, was your age with a similar driving record, and was with the same insurance company, you both got the same rate. Now a secret black box in a secured room at each insurance company cooks up an individual rate just for you. "

Here's a look, in no particular order, at some of the biggest variables that affect your car insurance rate.

Your credit score. Insurance companies care - quite a lot, actually - about that three-digit number when determining a rate.

"Most people are very surprised credit is a factor," said Laura Adams, a senior analyst for insuranceQuotes.com. "Studies have shown that people with poor credit file more claims."

Only three states - California, Massachusetts, and Hawaii - have made it illegal for insurance companies to check credit scores in determining auto premiums.

What type of car do you drive? Henry said more expensive cars, such as Audis or BMWs, can cost more to insure because of the higher costs to replace them if they're stolen. They can also be more expensive to repair.

However, Adams has found that vehicles that score high on car safety tests also typically lead to lower rates. Although SUVs and pickup trucks typically cost more to buy than an average car, the rates are often lower because they're generally safer vehicles.

Driving record and accident history. If you've been involved in an at-fault accident or received any moving violations, your rate will likely be higher than someone who is never pulled over and avoids accidents.

"Insurance companies look for any reason that you might be a risky driver," Adams said. "If you're more likely to cause an accident, your rates will go up."

Adams added that at-fault accidents typically are wiped from your record after three to five years, but DUIs can affect insurance rates for the next 10 years.

Your age, marital status and gender all matter. Personal information, most notably your age, can greatly affect your monthly premium.

For example, a married woman over the age of 25 typically pays less on auto insurance than, say, a single man under 25, based on statistical averages. Women overall typically pay less than men on insurance.

Being married also means extra savings compared to single men and women.

Are you currently insured? Henry says uninsured drivers can be placed in a "high risk, high cost insurance pool" when they do try to purchase a plan.

Where you live, miles driven. Where you live plays a large role in factoring an insurance rate.

"A populated area can lead to more theft and vandalism," Adams said.

Driving in busy metro areas can also lead to an increase in accidents, which will raise your rates.

Adams says driving more than 15,000 to 20,000 miles a year can also lead to higher rates.