Most of the reason for the driving percentage dropping was gas prices;It began to get to high,President Obama tried to do something about it as much as he could."President Obama's ambitious goals to curb the United States' greenhouse gas emissions,unveiled."Fewer cars were seen on the roads driving,"recent studies suggest that Americans are buying fewer cars,driving less and getting fewer licenses as each year goes by."It caused people to not drive their cars and take public transortation or not go anywhere at all.