The contract periods for recent PPP projects in the host nations generally range from 30 to 40 years. Portugal tends to use a standard period of 30 years for its concessions. While Spain has used concessions as long as 75 years in the past, current arrangements vary from 25 to 40 years. The government sets the period based on what term makes sense economically. In the United Kingdom, the Highways Agency has set recent contracts at 30 years. In Australia, the contract period is often a bid variable. In the case of the AirportLink/ Northern Busway project, the proposed and accepted term is 45 years.