The most important bus lines have frequencies of between 3 and 15 minutes during the day and between 10 and 40 minutes at night; most lines have service throughout the night. The bright yellow buses are known simply as 'guaguas'. The unique tariff, paid directly to the driver, is 1.30 euro. A 10-ride ticket is available for €7.50 at official shops in the city. The Tarjeta Insular (Island Card) which offered a 20% discount on both municipal buses and Global buses was discontinued on 1 January 2011.