Northern Ireland's love affair with Dublin Airport may be on the wane as figures show a decline of 30,000 in numbers of travellers from across the border using the airport.
The figure of 920,000 for the 12 months from April 2017 to March 2018 is also down 70,000 on the figures for calendar years for 2016 and 2017.
Numbers of local people using Dublin Airport - according to the NI Statistics and Research Agency's (Nisra) air passenger flow report - reached 990,000 in 2016, and fell to 950,000 in 2017.
A spokesman for Dublin Airport said: "The information in the Nisra report doesn't tally with our own data, which shows that the number of Northern Ireland residents using Dublin Airport in 2017 was just under 1.2 million.
"In the first half of this year, Dublin Airport's traffic from Northern Ireland-based residents has increased by 9%."
In addition, comparisons between full calendar years and a rolling 12-month period of four three-month periods were not valid, he added.
Meanwhile, Belfast International and George Best Belfast City have both seen their numbers hold steady between the calendar year of 2017 and the rolling 12 months to March 2018, at 3.68 million and 1.34 million respectively.
But a comparison of the calendar years of 2016 and 2017 reveal a fall in Belfast City Airport's numbers from 1,360,000 to 1,340,000.
In the same period, Belfast International figures grew from 3,200,000 to 3,680,000.
No one from Belfast City Airport could be reached for comment, but it's understood figures reflect the impact of cuts to Aer Lingus' summer schedule. A Flybe route to London City is thought to be a strong performer.
In response to the figures, a Belfast International Airport spokesman said: "These figures are heartening, and the upward trend is continuing."
But it said that suspending air passenger duty - a tax payable here on short-haul flights but which does not apply in the Republic - would help performance.
"An increase of this size makes us the best performing airport in Northern Ireland and points to what is possible if we convince the Government of the need to get rid of air passenger duty, which inhibits expansion and growth.
"Indeed, in the first half of 2018, passenger numbers were up 3.6% over the corresponding period of last year."
He added: "This is our busiest summer season ever with monthly double digit growth in July and so far in August, and we expect that by the end of the year, we will easily surpass our target of 6.1 million passengers."
But he said it was "worrying" that Northern Ireland was losing passengers to the Republic, where there is no air passenger duty on flights. According to Nisra, a total of 970,000 local passengers used airports in the Republic in 2017.
"It's worth reminding the Government that losing one million passengers denies the creation of upwards of 800 new jobs, and that is unacceptable."
The International Airport faced problems this week when it emerged that passengers' cars where damaged in a flood in one of its car parks during July.
But airport managing director Graham Keddie hit out at claims that up to 1,000 vehicles were damaged, and said that the real figure was just 35.