Car insurance is a necessary evil, but it doesn't have to be as expensive as it often is. Here are five things that can increase the cost of car insurance by as much as 93%:

1. Driving history
Your driving history, specifically your history of traffic infractions, has the potential to exert the biggest influence on the size of your car insurance premiums.

Not all infractions are created equal. From the perspective of an insurance company, as well as the authorities, certain moving violations are more serious than others.

A recent study by Quadrant Information Services found that a ticket for driving under the influence or driving while impaired increases a driver's premiums by an average of 93%. This is followed by reckless driving, which ups one's rates by an average of 83%. Finally, speeding tickets and other less serious offenses lead to average increases of 20% to 30%.

2. Claims history
While your claims history isn't as harmful as your driving history, making just one claim can hike your premiums by up to 76%.

A separate study by Quadrant Information Services found that a single auto insurance claim of at least $2,000 causes an average premium increase of 41%. A second claim in the same year generates an average premium increase of 93%.

The significance of the increase depends in part on where you live. In Massachusetts, a single claim increases a driver's premiums by an average of 76%. But in Maryland, which is on the other side of the spectrum, the average jump is only 22%.

3. Age
In addition to things you do, certain immutable traits also play a role in the size of your car insurance premiums. First and foremost is your age.

Generally speaking, younger people pay more for car insurance than do older people. This follows from the fact that beginning drivers have less experience than seasoned drivers and, not surprisingly, account for an outsized percentage of car accidents.

According to the Centers for Disease Control and Prevention, people aged 15-24 make up only 14% of the U.S. population, but they account for 30% of the total costs of motor vehicle injuries among males and 28% of the total costs of motor vehicle injuries among females.

It's for this reason that the typical 20-year-old driver pays 41% more for car insurance than does a 25-year-old, according to another analysis by Quadrant Information Services. These costs decline by an average of 18% over the next 35 years until a person reaches age 60, at which point the trend reverses and insurance costs begin to climb again.

4. Gender
A second largely immutable trait that factors into the size of your car insurance premiums is your gender.

Early on, this favors females. An average 20-year-old male, for instance, pays an estimated 23% more in premiums than an average 20-year-old female, according to Quadrant Information Services.

But not only does this level off with age, it actually reverses, leading to lower premiums for male drivers between the ages of 30 and 60 relative to their female counterparts.

5. Marital status
Last but not least is one's marital status, which is effectively just as important as age and gender when it comes to car insurance premiums.

"Marriage really does make people more careful and responsible," said Eli Lehrer, president the R Street Institute. Thus, "it isn't at all surprising that this translates into better driving behavior."

As shown in the chart below, irrespective of age, married men (and the same is true of women) pay less for car insurance than single men (and women).

The takeaway on car insurance
Your car insurance premiums are a function of both controllable and uncontrollable factors. Thus, if you want to decrease them, then you'll have to focus on the former.

There is no magic bullet. The key is simply to eradicate all traffic infractions and eliminate any claims. Beyond that, shopping around and comparing rates and coverage options is the only sure step you can take to minimize the cost of car insurance.