Allstate investors probably wish they'd bought some insurance of their own.
Shares of the insurance company fell 10 percent Tuesday after it missed earnings and revenue expectations in a report after Monday's bell that showed a 41 percent drop in second-quarter operating income versus the year-ago period.
The apparent culprit was an increase in the number and severity of car accidents, which CEO Thomas Wilson called "broad-based" and therefore clearly "driven by external factors" in the company's earnings release.
Allstate President Matthew Winter went into more detail on the earnings call, telling analysts that "miles driven and Allstate's auto claim frequency have historically been very tightly correlated with one another. ... While miles driven isn't the sole driver of our increased loss trends, it does explain a significant amount of the result. And as miles driven have continued to increase rapidly over the prior year, as the year has progressed."
Interestingly, then, bad news for Allstate looks suspiciously like good news for America.
"Typically accidents do go up when people are driving more. And that often happens when people are going on their summer vacations and spending more time in their cars, so it actually could be a positive sign for the economy," Nomura analyst Clifford Gallant said in a Tuesday "Trading Nation" interview.
On the other hand, the connection between overall miles driven and accident frequency and severity may not be as close as the company would have investors believe. For example, Travelers reported seeing regular frequency and severity in auto accidents in the second quarter, despite the increase in miles driven and decrease in unemployment.
"We know that there is a connection between miles driven and number of car accidents. The problem is that for many, including myself, it is very easy to look at the data of miles driven and decide that there's going to be a one-to-one connection—and unfortunately, it just doesn't work out that way," Sandler O'Neill analyst Paul Newsome told CNBC in a phone interview.
"What's happening with Allstate does seem to be happening only to Allstate, and so it appears to be less about miles driven and more about something else," the analyst said.
Potential explanations provided by Newsome include a faulty underwriting model, or an unfortunate situation by which Allstate's competitors "are able to cherry-pick the better auto claim drivers away from them."
"Of course, it can also be random," he added.
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