Mass adoption of autonomous vehicles should begin ramping up in 2023 and will ultimately drive a shift in vehicle ownership from consumers to larger mobility service providers with large fleets of battery-electric, autonomous vehicles, according to a new study from Cox Automotive.

This shift is expected to eventually lead to a 40% decline in consumer vehicle sales, as mobility models gain larger adoption for carsharing, ride-hailing, subscription services, and other services that gradually supplant consumers as the primary owners of vehicles by 2034.

The findings come as part of the 2018 Cox Automotive Evolution of Mobility study, which the company released on Aug. 16.

The study's findings about future trends somewhat bely current consumer attitudes about autonomous vehicles. While those who participated expressed increasing awareness of autonomy, they also expressed greater worries about their safety since the last Cox survey in 2016. The study attributed the safety worries to awareness of several high-profile accidents involving autonomous vehicles operated by Uber and Waymo. Respondents were 19% more aware of fully autonomous vehicles with or without a human operator since 2016.

Only 16% of respondents said they would feel comfortable riding in a fully autonomous vehicle without the option of being able to take control. Respondents also increasingly believe roadways wouldn't be safer with autonomous vehicles — 18% fewer said roadways would be safer if vehicles were fully autonomous.

Nearly half of respondents (a 19% increase) said they would never buy a fully autonomous vehicle, an opinion that skews older. While 71% of baby boomers said they wouldn't buy one, 56% of Gen X, 39% of millennials, and 48% of Gen Z said they wouldn't buy one. Urban dwellers are more open to autonomy than suburbanites or rural residents.

However, respondents also expressed interest in semi-autonomous features for their next vehicle purchase. They singled out collision warning and avoidance, adaptive headlights, lane keeping assist, and adaptive cruise control as the most popular driver-assisting features. Most respondents listed the features as "nice to have" rather than "must have."