Imagine the typical American family.

Odds are your vision includes a home with two kids, as well as two or more cars.

But according to a new study by KPMG, that image is becoming a less common reality. As a growing number of consumers participate in car sharing, wait longer to buy their first vehicle and move to the suburbs, KPMG predicts that in about 25 years, fewer than half of U.S. households will own more than one vehicle.

"We think that the two-car family, over time, it is not going to go down to zero, but a significant amount of people are going to reduce that number," said Gary Silberg, a partner at KPMG who conducted the study.

According to the report, 57 percent of American households currently have two or more cars. Although that percentage has held relatively steady over the last couple of decades, Silberg forecasts it will fall to 43 percent by 2040. That's thanks, in part, to the growing popularity of ride-share companies.

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"It is already happening right now. Look at the number of Uber drivers and Lyft drivers," Silberg said. "We think the shared economy is going to be the economy of the future, certainly in automotive."