Just as safety authorities were lauding the decrease in automobile driver fatalities and lamenting the unchanged motorcycle rider fatalities for 2011, we get news that traffic deaths have risen overall in Q1 of this year by a whopping 13.5 percent. The National Highway Traffic Safety Administration puts traffic fatalities at 7,360 people, a rise from 6,720 in the same period last year and representing a jump from 0.98 deaths to 1.10 deaths per 100 million miles traveled. The National Safety Council has even higher numbers , declaring there were 8,170 deaths the first three months of this year compared to 7,270 last year.No one is yet sure of the reason for the jump. A portion of the blame has been put on the warmer-than-usual winter that had led to more people driving. Overall mileage was down in 2011 compared to 2010 by 1.2 percent or 35.7 billion miles. But total driven miles of Q1 this year increased just 1.4 percent. This year's number is even higher than the Q1 number from 2010 , when 6,690 traffic deaths were reported by the NHTSA , yet it's still less than every year from 2005-2009. The improving economy has also been cited as a factor.Importantly, though, NHTSA said that due to special factors the fatality rate so far this year "should not be used to make inferences for the fatality rate for the whole of 2012."