Kei car (or keijidōsha, kanji: 軽自動車, "light automobile", keːdʑidoːɕa), refers to the Japanese vehicle category for the smallest highway-legal passenger cars, with restricted dimensions and engine capacity. Similar Japanese categories exist for microvans and kei trucks. These vehicles are most often the Japanese equivalent of the European Union's A-segment "city cars". The kei category was created by the Japanese government in 1949, and the regulations have been revised several times since. These regulations specify a maximum vehicle size, engine capacity, and power output, so that owners may enjoy both tax and insurance benefits. In most rural areas, they are also exempted from the 車庫証明書 parking space ownership requirement (as street parking is usually prohibited in Japan). Kei cars have become very successful in Japan, consisting of over one-third of domestic new-car sales in fiscal year 2016, despite dropping from a record 40% market share in 2013 after the government increased kei car taxes by 50% in 2014. In 2018, seven of the 10 top-selling models were kei cars, including the top four, all boxy passenger vans: the Honda N-Box, Suzuki Spacia, Nissan Dayz, and Daihatsu Tanto. In export markets, the genre is generally too small and specialized for most models to be profitable. Notable exceptions exist, for instance the Suzuki Alto and Daihatsu Cuore, which have been exported consistently from around 1980. Kei cars are not only popular with the elderly, but also with youths and younger families because of their affordability and ease of use. Nearly all kei cars have been designed and manufactured in Japan, but a version of the German-made Smart Fortwo was briefly imported and officially classified as a kei car, and since then, the British Caterham 7 160 has also received such classification. Kei cars feature yellow license plates (with black numbers on a yellow background for private use, and yellow numbers on a black background for commercial use), earning them the name "yellow-plate cars" in English-speaking circles.