Automakers should be able to increase global sales of fully autonomous vehicles to 33 million by 2040 from 51,000 in 2021 — the first year of significant volume, according to a forecast from IHS Markit.

There should be 7.4 million autonomous vehicles operating in the U.S. in 2040, the forecast found.

This dynamic growth is expected to be enabled by ride hailing and other mobility services, according to the forecast. The U.S. will lead the world in early adoption and initial deployment of the vehicles, which could arrive as early as 2019. Europe and China are expected to add considerable volume starting in 2021.

"The first autonomous vehicle volumes — beyond retrofit test vehicles — will arrive in 2019 through driverless mobility services," said Egil Juliussen, director of automotive technology research at IHS Markit. "Volumes will surpass 51,000 units in 2021 when personally owned autonomous cars reach individual buyers for the first time, and IHS Markit forecasts estimate nearly 1 million units will be sold in 2025 across shared fleets and individually owned cars."

The units will be fully autonomous Level 4 or Level 5 vehicles based on the standard set by the Society of Automotive Engineers.

In the coming years, transportation will be driven by on-demand services rather than the individual ownership model and the industry will provide vehicles based on usage per distance or time rather than unit sales, according to the firm.

General Motors, Waymo, and Uber are expected to contribute significantly to mobility fleet volumes as early as 2019.