Drivers in Louisiana and Michigan are hit hardest when it comes to car insurance premiums, while those in Maine and Iowa pay the least, according to Insure.com's annual rankings.

According to Amy Danise, editorial director of Insure.com, one reason for higher car insurance premiums in Louisiana, about $2,699 per year on average, is the high number of bodily injury claims filed after car crashes in the state.

Michigan's high premiums are a result of the state's guarantee of unlimited, lifetime personal injury protection benefits for treatment of injuries from a car crash. This requires insurance companies to cover the first $500,000 in medical treatments while a state-created nonprofit, Michigan Catastrophic Claims Association, reimburses medical expenses beyond that amount. Michigan drivers are hit with an annual fee for the catastrophic claims fund. In 2013 that fee is $175 per vehicle.

As for the least expensive states, Insurance.com credits “rural sensibilities” and lower population density with the lower costs in Iowa. Maine offers similar characteristics and a graduated licensing program that limits young drivers, likely reducing the rate of crashes.

To get the numbers, Insure.com looked at auto insurance rates for more than 750 car models from six large carriers -- Allstate, Farmers, GEICO, Nationwide, Progressive and State Farm -- in 10 ZIP codes per state.

By averaging the rates for all vehicles in each state, Insure.com was able to come up with its rankings. This is the third year the survey has been conducted.

Rates are for comparative purposes within the same model year and are based on insurance for a single, 40-year-old male who commutes 12 miles to work each day, with policy limits of 100/300/50 ($100,000 for injury liability for one person, $300,000 for all injuries and $50,000 for property damage in an accident) and a $500 deductible on collision and comprehensive coverage. The hypothetical driver has a clean record and good credit. The rate includes uninsured motorist coverage. Actual rates will depend on individual driver factors.

Here are Insure.com's rankings for the 10 most expensive and 10 least expensive states for car insurance. See the full list here.

(average annual premium)

-- Louisiana: $2,699

-- Michigan: $2,520

-- Georgia: $2,155

-- Oklahoma: $2,074

-- Washington, D.C.: $2,006

-- Montana: $1,914

-- California: $1,819

-- West Virginia: $1,816

-- Rhode Island: $1,735

-- Kentucky: $1,725

-- Maine: $934

-- Iowa: $1,028

-- North Carolina: $1,085

-- Ohio: $1,106

-- New Hampshire: $1,112

-- Idaho: $1,133

-- Vermont: $1,176

-- Indiana: $1,183

-- Washington: $1,226

-- Arizona: $1,227

-- Sherrice Gilsbach

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