Volvo made big headlines Wednesday when it became the first traditional automaker to announce that all of its cars would be at least partially electric in 2019. The trend away from old-school engines may seem inevitable, but the Wall Street Journal has a sobering stat for electric advocates: Less than 1% of the more than 17.5 million vehicles sold in the US last year were all-electric. That probably won't change unless gas prices rise, charging stations multiply, and government subsidies remain in place. Other developments: