A person who protested about noise at Dublin Airport almost 8,000 times last year contributed to a 10-fold increase in complaints.
The individual accounted for more than half of the total of 15,160 complaints, up from just 1,453 in all of 2018.
And along with another person, they made up almost three-quarters of the total.
Figures published by Dublin Airport Authority show there was an average of 42 complaints a day.
But the prolific complainant from Ongar in north west Dublin made a total of 7,786 complaints - a daily average of 21. This included 4,554 in July alone when he lodged an average of 147 complaints each day.
The other individual filed 3,435 noise complaints.
The DAA said the large increase in complaints last year was skewed by the multiple complaints made by a number of individuals.
An airport spokesperson said the DAA had engaged directly with the two individuals who had made the most numerous complaints.
"Aircraft noise is subjective and is personal to each individual," the spokesperson said. He pointed out that the number of different individuals who made a complaint during 2019 declined by 3pc to 284 from 293 the previous year. The biggest number of complainants came from Swords (37) followed by Portmarnock (27), Hollystown (25), St Margaret's (20) and Tyrrelstown (13).
The spokesperson added: "The level of aircraft noise is dependent on the type of aircraft and the number of flights.
"While the number of flight movements at Dublin has increased in recent years, the advent of newer, quieter aircraft has brought about substantial reductions in aircraft noise."
He pointed out that, for example, the new Airbus A320Neo aircraft that was introduced by Aer Lingus last year generates 50pc less noise than the previous model of the same plane.
According to the DAA, more than 95pc of aircraft using Dublin Airport since 2015 were the quietest type of aircraft compared to 83pc in 2008.
The DAA spokesperson said the reduction of aircraft noise in neighbouring communities was the joint responsibility of Dublin Airport, the Irish Aviation Authority and airlines.
"DAA works closely with all those stakeholders to minimise aircraft noise at the airport," the spokesperson said.
Figures show that 88pc of complaints last year related to aircraft departures from the main runway taking off in a westerly direction.
The spokesperson said DAA was acutely aware of the concerns of local residents in relation to noise and engaged with them on an ongoing basis. "A balance has to be achieved between those concerns and the needs of the Irish economy," he added.
Official figures show that 99.2pc of commercial aircraft using Dublin Airport last year kept to the correct flight path on approach and take-off.
Under a noise management plan, most aircraft taking off from Dublin Airport's main runway must maintain a straight course for five nautical miles before commencing a turn unless otherwise permitted by air traffic controllers.
The DAA operates a €1m noise and flight track monitoring system to ensure minimum disruption to local communities, which includes eight fixed noise monitoring terminals around north Dublin and one mobile monitor.
It said all aircraft operating at Dublin Airport conform to current standards regulated by the International Civil Aviation Organisation.
"As older aircraft are phased out in the short term, this situation will continue to improve," the spokesperson added.