Except in 2019, according to the CAA, the airport handled 18,213,901 while the airport claimed the figure was 17,999,969 just 31 passengers inside the legal limit, which was very convenient as the airport operated at 99.99982% of its planning limit.
https://www.caa.co.uk/Documents/Down...e0b5b3307/1330
https://www.london-luton.co.uk/Londo...c5e683c5fe.pdf
Those with a suspicious mind could be thinking that it was a deliberate act to create numbers to comply with planning permission while others might have thought it was magic that the airport could make 213,932 passengers just disappear while no one was looking, particularly the planning authority who asked no questions and just said nothing while taking their cut.