Answer (from NY Times; subscription): 78% or $671!
More from the Times article:
An annual analysis by insuranceQuotes.com, a rate comparison site, found that adding a teenager still increased annual premiums substantially, but the magnitude of the increase has been falling over the past few years.
Adding a single teenager to a policy caused annual premiums to increase an average of 78 percent, or $671. But rate increases have been decreasing since 2013, when the average increase was 85 percent.
Laura Adams, senior insurance analyst with insuranceQuotes, said that factors in the trend may include safer automobile technology, a dip in the number of teenagers getting driver’s licenses and the continued impact of “graduated” driving programs, which place restrictions on new drivers until they gain more experience on the road.
So, what strategies can your students use to minimize this cost? The article offers a few: