Another top selling NEV is the Renault Twizy heavy quadricycle, launched in March 2012, with global sales of 15,000 units through April 2015. The Twizy was the top-selling plug-in electric vehicle in Europe during 2012. , a total of 18,592 units had been sold in Europe, representing 96.1% of global sales. Global sales since inception totaled 21,874 units through December 2018. Sales of low-speed small electric cars experienced considerable growth in China between 2012 and 2015 due to their affordability and flexibility because they can be driven without a driver license. Most of these small electric cars are popular in small cities, but they are expanding to larger cities. A total of 200,000 low-speed small electric cars were sold in China in 2013, most of which are powered by lead-acid batteries. These electric vehicles not considered by the government as new energy vehicles due to safety and environmental concerns, and consequently, do not enjoy the same purchase benefits as highway legal plug-in electric cars. In 2015, sales of low-speed small electric passenger vehicles in China totaled 750,000 units, and 1.2 million in 2016. , the stock of low-speed small electric car was estimated to be between 3 million and 4 million units. However the sales ratio between LSEVs and passenger NEVs began to decrease beginning in 2015. In 2014, LSEVs sales were 15 times more than normal plug-in passenger cars, but the ratio declined to about four times in 2016, and fell to 2.5 times in 2018, when about 1.1 million normal passenger electric vehicles, compared to 1.4 million low-speed vehicles.