After declining for decades, traffic deaths have been rising for the last two years.  Compared to 2015, fatalities on the road have increased an alarming 14.4%.  And while statistics on "distracted driving" are poor, many experts believe that the use of mobile devices while driving may be a significant factor in the increase.

Bloomberg:

Over the past two years, after decades of declining deaths on the road, U.S. traffic fatalities surged by 14.4 percent. In 2016 alone, more than 100 people died every day in or near vehicles in America, the first time the country has passed that grim toll in a decade. Regulators, meanwhile, still have no good idea why crash-related deaths are spiking: People are driving longer distances but not tremendously so; total miles were up just 2.2 percent last year. Collectively, we seemed to be speeding and drinking a little more, but not much more than usual. Together, experts say these upticks don't explain the surge in road deaths.

There are however three big clues, and they don't rest along the highway. One, as you may have guessed, is the substantial increase in smartphone use by U.S. drivers as they drive. From 2014 to 2016, the share of Americans who owned an iPhone, Android phone, or something comparable rose from 75 percent to 81 percent.

The second is the changing way in which Americans use their phones while they drive. These days, we're pretty much done talking. Texting, Twitter, Facebook, and Instagram are the order of the day – all activities that require far more attention than simply holding a gadget to your ear or responding to a disembodied voice. By 2015, almost 70 percent of Americans were using their phones to share photos and follow news events via social media. In just two additional years, that figure has jumped to 80 percent.

Finally, the increase in fatalities has been largely among bicyclists, motorcyclists, and pedestrians – all of whom are easier to miss from the driver's seat than, say, a 4,000-pound SUV – especially if you're glancing up from your phone rather than concentrating on the road. Last year, 5,987 pedestrians were killed by cars in the U.S., almost 1,100 more than in 2014 – that's a 22 percent increase in just two years.  

The National Highway Transportation Safety Administration has attributed only 448 traffic deaths to cell phone use out of more than 32,000.  That makes drunk driving 23 times more likely to be a cause of death on the highways than cell phone use.

But studies have shown that a driver is just as impaired while using a smartphone on the road as when drinking.  So the question isn't if smartphones use causes traffic fatalities; the question is how many.

Starting in the 1980s, the government instituted a massive education program about the dangers of driving while drinking.  At the same time, states passed laws that made DUI a serious offense with mandatory jail time for repeat offenders.  The combination did the trick.  Road fatalities were nearly cut in half over the last three decades.

Now they're on the rise again.  I don't think we can say for sure that "distracted driving" is the primary reason for the spike in traffic deaths.  But it certainly bears more investigation.  And some way must be found to gather more accurate statistics about distracted driving deaths.