All lines can be used with the Oyster card used across London. The London Overground has received praise for its transformation of long-neglected lines into clean and reliable services, with passenger usage increasing sharply such that trains had to be extended from 3 cars in 2007 to 5 cars in 2015. In the autumn 2011 National Passenger Survey, London Overground received an overall satisfaction rating of 92%, a 7% improvement on the previous survey.