– Ford is shifting all North American small-car production to Mexico, CEO Mark Fields told investors Wednesday.

"Over the next two to three years, we will have migrated all of our small-car production to Mexico and out of the United States," Fields said.

The auto industry has known for decades that domestic manufacturers struggle to make a profit on small cars. Shifting assembly to Mexico can reduce costs to a point. But some of these cars are over-engineered.

For example, Field said the current Ford Focus can be ordered in 300 different configurations of options and colors. Ford wants to reduce that number to 30, which will make the production process simpler and less expensive. Americans increasingly prefer larger vehicles, especially pickups, higher-riding SUVs and crossover vehicles for their personal use.

The future of smaller cars in the U.S. might depend on the ability to electrify their powertrains and introduce them to ride-sharing fleets where they can generate revenue from fares paid by multiple riders.

Along those lines, Fields and other Ford executives outlined an aggressive $4.5 billion investment plan that will unfold over the next four years. The investment will result in new models in segments such as commercial vehicles, trucks, SUVs and performance vehicles, the execs said.

Ford also reiterated its commitment to developing an autonomous vehicle by 2021. The company believes that autonomous vehicles could account for up to 20 percent of vehicle sales by 2030.

The day's announcements came as Ford gave a presentation on corporate strategy to more than 100 analysts and investors. The meeting came as the U.S. auto industry's six-year recovery is cooling and the United Kingdom's exit from the European Union has presented a new challenge to Ford's rebound in Europe.

Then there is the high-stakes competition to develop and refine fully autonomous vehicles that initially will be used in ride-sharing services.

Ford shares have fallen 12 percent from the beginning of the year from $14.09 to $12.14 at Wednesday's close. Fields spent the first half of his 45-minute presentation assuring analysts that Ford's core business remains strong, especially in its most profitable segments such as full-size pickup trucks, commercial vans and its resurgent Lincoln luxury brand.

But he also said the company must respond to a global shift away from personal vehicle ownership to one in which personal ownership will be challenged by on-demand shared mobility.

"This is very different thinking for us," Fields said. "For most of our history we have thought about the thing and how many of the things we have sold."

In exploring how a traditional manufacturer can profit in a market where the vehicle becomes a service platform, Fields said the first question he and fellow executives had to define is, "What's our point of view on autonomy?"

"We see huge social economic and environmental benefits. We're focused on usage where miles traveled will be," he said. "Autonomous vehicles will account for one of every 10 miles traveled by 2025, and will grow from 5 percent of all vehicles sold in the U.S. in 2025 to 30 percent in 2030."