Double Decker is a bus type designed to carry large groups of people. It has two passenger decks, the upper deck for passengers only, and the lower deck for passengers and/or luggage compartment. Doubledeckers are often the most cost-efficient bus type, considering the larger passenger capacity, and the same or slightly higher costs of fuel, staff, toll... There are doubledeckers with the capacity of over 80 passengers, meaning that this bus can practically substitute two starndard 50-seater charter buses. One of the most popular doubledeckers manufacturers is the AEC - Associated Equipment Company, a United Kingdom based manufacturer which built the famous London public transport doubledeckers until 1979. Today, there are many bus manufacturers that produce doubledecker coaches, mostly in the European Union, such as Setra, Neoplan, Ayats etc.