The number of civilian pilots certified to operate unmanned aerial vehicles — known as UAVs or drones — and training centers has soared over the past four years, according to an industry report released on April 18.

As of the end of 2017, China had 199 qualified training centers for civilian drone pilots and issued 24,407 certificates, according to a report issued by the Aircraft Owners and Pilots Association of China, a nonprofit organization.

In 2014, China had just 18 such training centers. The number of certificates issued rose by more than 50 percent in the second half of last year. As of July, the association had issued 15,545 certificates.

“It shows that drones can be used in diverse businesses, which brings great convenience and incomparable advantages over manned aircraft,” said Wang Xiazheng, director of the association’s department that deals with unmanned aircraft.

The China Civil Aviation Administration authorized AOPA-China to issue licenses beginning in 2015. The administration requires licenses for people operating unmanned aerial vehicles heavier than 7 kilograms.

The report also found that about 60 percent of pilots are 24 to 32 years old, and more than 95 percent are male.

The development of drones has boomed since 2014. China produced nearly 450,000 drones in 2016, and the total likely hit 500,000 in 2017, according to Wu Renbiao, vice-president of Civil Aviation University of China in Tianjin.

“There are around 3 million drones worldwide, 75 percent of which were made in China,” Wu said in an earlier interview with China Daily.

The scale of China’s unmanned aerial vehicle market will likely grow at an annual rate of 30 percent between 2017 and 2021, Li Jian, deputy director of the administration, said at a conference in March.

The rapid development also comes with a downside. Civil aviation has occasionally been interrupted by unmanned aircraft. Last year, the administration reported 19 illegal drone flights around Chinese airports in May, which affected 326 commercial flights.

That prompted the administration to introduce regulations requiring real-name registration of drones weighing more than 250 grams. As of March this year, more than 180,000 drones in civilian use had been registered under real names.

Thanks to the new measures, incidents of commercial air travel disruptions have been significantly reduced, the authorities said.