The Federal Aviation Administration reports nearly 1.5 million drones are registered in the United States, nearly a third of them being used for commercial purposes, and the numbers are increasing quickly.

In a report issued earlier this month, the FAA reported 416,210 drones registered for commercial use, a 50% increase over the 277,000 registered at the end of 2018, and 1.08 million registered for recreational purposes. There also are 158,554 certified remote pilots.

At the end of 2018, registered commercial and recreational drones numbered 900,000.

U.S. businesses are using drones for not only photography, but for everything from data compilation to package delivery to tracking criminal suspects. And the FAA admitted it seriously underestimated the number of drones that would be in use this year. It originally expected the number to hit 450,000 by 2022. Now the 2022 projection could top 1 million.

“We anticipate that the growth rate … will continue to accelerate over the next few years,” the FAA said in its 2019-2039 forecast. Between 2017 and 2018, monthly registrations of drones grew from 4,600 a month to 14,600, a pace that increased again in 2019.

“The significant growth in this sector over the past year demonstrates the uncertainty and potential of the market,” the forecast said, predicting the number of drones will triple by 2023 as the devices gain efficiency and safety, and battery life expands.

Barclays estimates the drone market will grow to $40 billion in five years, resulting in cost savings of $100 billion.

Much of the growth is fueled by the open-source platform for writing software developed by Auterion, a Swiss-American start-up.

 “We partnered with Auterion because they solve so many parts of our problem in software,” Spencer Gore, chief executive of American drone maker Impossible Aerospace, told the Financial Times. “They are the experts. There is no sense in us reinventing the wheel.”

The World Economic Forum touts drones for fighting climate change, promoting their use in everything from mapping wildfires to measuring jellyfish populations.

However, Narayan Iyer of Cognizant said there are a number of obstacles preventing more widespread use of drones, including the fragmented state of flight regulations and security protocols. Iyer told Manufacturing and Engineering Magazine European regulators have done the most in trying to develop cohesive safeguards.

Another obstacle is developing technology to make drones identifiable in the same way airplanes and helicopters are, as well as lighting, which is a drain on battery life,  Iyer said. A third problem, he noted, is the lack of imagery to enable artificial intelligence to learn while still flying.