“The industry spent $5.7 billion on advertising and allowances in 2011, but this increased spend does not appear to have generated a commensurate increase in market churn,” observes Bowler.

Asked why fewer consumers are shopping this year, Bowler suggests insurers may have exhausted the appetite of “serial shoppers.” He notes that those who have shopped in recent years on the promise of saving hundreds of dollars might have found such savings initially, prompting them to shop again the next year. However, upon shopping a second time, those consumers may have found that they did not save hundreds more. This, Bowler suggests, may make them hesitant to try shopping a third time.

Bowler also says customer satisfaction could impact shopping habits. In J.D. Power's last auto-insurance-satisfaction survey, Bowler says overall customer satisfaction was 790 on a 1,000-point scale. That was a 13-point increase over 2010. He points out that when industry satisfaction improves, the rate of shopping tends to decline.

However, for those consumers who did shop over the last 12 months, 43 percent switched providers, the highest rate since 2008, when J.D. Power began measuring retention, and a 3 percent increase over last year's survey.

“The increase in the proportion of shoppers actually switching suggests that fewer price-checkers are gathering quotes they are less likely to act upon, perhaps a direct result of the lower typical savings derived from switching, which has decreased from an average of $412 in 2010 to only $359 in the past 12 months,” says Bowler.

Regarding how consumers are shopping, J.D. Power says 52 percent of consumers start their auto-insurance-shopping process online, and 73 percent visit at least one insurer's website at some point during the shopping experience.

“More significantly,” says J.D. Power, “32 percent of customers solely obtain quotes online, and today 34 percent of all recent shoppers state they would most prefer to purchase their new policy online.”

Bowler says consumers today expect to be able to visit an insurer's website and then complete their purchase in the same visit. “In most cases, shoppers can compare many policies online and narrow down their search field entirely via this self-service paradigm,” he says. “From that point, they can then decide if they need to speak with an agent or to continue their online purchase process.”

As for consumers' satisfaction with their shopping experience at different auto-insurance providers, The Hartford ranked highest on J.D. Power's 1,000-point scale with a score of 857. J.D. Power says The Hartford “performs particularly well in policy offerings and price.” Liberty Mutual scored second with 850, followed by American Family (845), Auto Club Group (842), and Nationwide (841).

The industry's average score was 828.