Although there were just 3.1m electric vehicles on the world’s roads by the end of last year, that number is rapidly increasing. As the chart shows, there was over 50% growth between 2016 and 2017, which was a larger percentage increase than in previous years. Should this exponential growth curve continue, it’s likely that before the year is out there will be close to five million electric vehicles in use across the globe. In the US, electric vehicles benefit from subsidies in a number of states, which has contributed enormously to their popularity. China, meanwhile, is already the world’s largest electric vehicle market and is home to a number of car startups that are looking to take on Elon Musk and Tesla.