Worldwide airline passenger numbers topped four billion for the first time last year as fares fell amid improving economic conditions.

Airlines carried 4.1 billion passengers on scheduled services, an increase of 7.3% over 2016, representing an additional 280 million trips by air, according to latest Iata figures.

Carriers in the Asia Pacific region flew the largest number of passengers at 1.5 billion, a rise of more than 10% over 2016, to give a market share of 36.3%.

Europe was next with a 26.3% market share representing 1.1 billion passengers, up 8.2% year-on-year.

North America was the third largest region, with numbers up by 3.2% to 941.8 million, followed by Latin America, the Middle East and Africa.

The ranking of passenger traffic by nationality saw the UK above fifth-placed Germany with 147 million, or 4.3% of the total, while the US was top, followed by China and India.

American Airlines was the top carrier ranked by total scheduled passenger kilometres flown at 324 million, above Delta Air Lines at 316.3 million and United Airlines at 311 million.

Emirates was fourth at 289 million followed by US low cost carrier Southwest at 207.7 million.

Star Alliance maintained its position as the largest airline grouping with 39% of total scheduled traffic, followed by SkyTeam (33%) and Oneworld (28%).

The top five busiest international routes were all in Asia, with Hong Kong-Taipei leading the list wit 5.4 million passengers.

Iata director general and CEO Alexandre de Juniac said: “In 2000, the average citizen flew just once every 43 months. In 2017, the figure was once every 22 months.

“Flying has never been more accessible. And this is liberating people to explore more of our planet for work, leisure and education. Aviation is the business of freedom.”