According to a recent report from the International Energy Agency (IEA), 2016 was a record year for electric vehicle (EV) sales. Over 750,000 EVs were sold worldwide last year, compared to 547,220 sold in 2015.

But the gains are overshadowed by the distance that electric cars still have to go—although more than 2 million EVs now travel the world’s roads, they only make up 0.2 percent of the total light-duty passenger vehicle share around the world. And the growth of the number of electric cars on the roads actually slowed in 2016 compared to 2015 (60 percent in 2016 versus 77 percent in 2015), leaving policy makers and sustainable growth advocates wondering how to continue to grow the global fleet to meet climate change mitigation goals.