10 states with the highest cost of adding a teen to an auto policy

It's no secret: Adding a teenage driver to an auto policy can be risky.

Teen drivers are often inexperienced, nervous and reckless. In fact, according to the Arlington, Virginia-based Insurance Institute for Highway Safety, the fatal crash rate per mile driven for drivers between the ages of 16 and 19 is almost three times higher than all other age groups.

Related: 10 people die every day during the summer from a crash involving a teen driver

Not surprisingly, adding a teen driver often causes a dramatic spike in annual auto policy premiums  so much so that they can even double in some areas. According to InsuranceQuotes.com, on average U.S. families who add a young driver to their auto insurance policy will see an annual premium increase of 79%.

For the fourth year in a row, InsuranceQuotes.com commissioned a study by Quadrant Information Services to examine the economic effect of adding a driver between the ages of 16 and 19 to a family's car insurance policy. According to the study, this year's average premium increase is down from last year's average of 80%, and is even lower than 2013, when the average increase was as high as 84%.

Related: Road trip! 7 safe-driving tips for new graduates

According to InsuranceQuotes.com, these gradual decreases speak to a larger trend in teen driver safety and fewer teens being behind the wheel. According to a study from the University of Michigan, 69% of 17-year-old Americans had a license 30 years ago. Today it's 45%.

Here are the 10 U.S. states where adding a teen driver to an auto policy is the most costly:

Related: Best used vehicles for teens

Tennessee is new to the top 10 most expensive states in 2016, just making the list at No. 10. (Photo: iStock) 

10. Tennessee

92.21% average auto insurance premium increase after adding a teen driver to a policy.

Last year, Vermont also ranked ninth, with a 94.99% increase. (Photo: Shutterstock)

9. Vermont

95.06% increase.

Connecticut moved down one spot this year. In 2015, the state ranked seventh, with a 98.31% increase. (Photo: Shutterstock)

8. Connecticut

96.33% increase.

Maine also makes the top 10 again this year, though it ranks lower than it did in 2015. Last year, Maine was fourth with an average premium increase of 102.76%. (Photo: Shutterstock)

7. Maine

99.13% increase.

Once again, Oregon comes as the sixth most expensive state to add a teen driver. In 2015, adding a teen driver averaged a 99.10% average increase to an auto policy. (Photo: Shutterstock)

6. Oregon

99.87% increase.

Ohio is new to the top 10 in 2016, coming in as the fifth most costliest state to add a teen driver. (Photo: iStock)

5. Ohio

100.17% increase.

This year Wyoming has fallen a couple of spots, from second to fourth most expensive state to add a teen driver. In 2015, the average premium increase in the state was 104.45%. (Photo: Shutterstock)

4. Wyoming

105.77% increase.

The price of adding a teen driver in Arizona has spiked from the previous year. In 2015, the Grand Canyon State ranked eighth, with an average premium increase of 95.89%. (Photo: Shutterstock)

3. Arizona

109.36% increase.

In 2015, Rhode Island ranked fifth, with an average premium increase of 101.76%. (Photo: Shutterstock)

2. Rhode Island

119.19% increase.

Once again, New Hampshire is the most expensive state to add a teenaged driver to an auto policy. The average increase is up nearly 11% from last year's average of 114.92%. (Photo: Shutterstock)

1. New Hampshire

125.39% increase.

Read on to to see the five least expensive states to add a teen driver to an Auto policy, as well as an interactive map with all 50 states' average premium increases:

5 least expensive states to add a teen driver

5. South Dakota: 59.32% increase.

4. Michigan: 57.60% increase.

3. North Carolina: 56.87% increase.

2. New York: 51.81% increase.

1. Hawaii: 16.93% increase.

(Hover your cursor over the states on the chart below to see the average premium increase from adding a teen driver for each state.)