Further information: Landing slot
British Airways aircraft at Terminal 5C
Until it was required to sell Gatwick and Stansted Airports, Heathrow Airport Holdings held a dominant position in the London aviation market, and has been heavily regulated by the Civil Aviation Authority (CAA) as to how much it can charge airlines to land. The annual increase in landing charge per passenger was capped at inflation minus 3% until 1 April 2003. From 2003 to 2007 charges increased by inflation plus 6.5% per year, taking the fee to £9.28 per passenger in 2007. In March 2008, the CAA announced that the charge would be allowed to increase by 23.5% to £12.80 from 1 April 2008, and by inflation plus 7.5% for each of the following four years. In April 2013, the CAA announced a proposal for Heathrow to charge fees calculated by inflation minus 1.3%, continuing until 2019.Whilst the cost of landing at Heathrow is determined by the CAA and Heathrow Airport Holdings, the allocation of landing slots to airlines is carried out by Airport Co-ordination Limited (ACL).