One week before National Small Business Week, a new study examines some surprising things that the millions of small businesses across the U.S. have in common.

A Pew Research Center Survey released Monday delved into Census Bureau data points associated with 33 million small businesses across the U.S. The study defined “small business” as a firm with less than 500 workers, with at least one location.

In the report, small businesses overwhelmingly shared one major commonality: they rarely had employees. In fact, 27 million, or about 82%, did not have any workers, and about 3 million businesses with employees only had one to four people on their payroll.

Still, small businesses employed 56.4 million people in 2021 and achieved more than $16.2 trillion in revenue. Larger businesses with more than 100 employees scored bigger pieces of the revenue pie, though they made up less than 1% of the overall picture.

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Also, most small businesses are not mom-and-pop shops, according to the survey. One in 10 businesses in the U.S. were equally owned and operated by spouses, and just 27% were family-owned overall.

It’s also not usually franchises. The majority of small businesses (95%) reported that they did not fully or partially operate as a franchise.

A majority of the businesses surveyed, almost three in five, have been running for at least six years, and 15% were operational for over a quarter of a century.

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Small businesses also share a positive public perception. Most Americans (86%) indicated that small businesses positively impact the country in a separate Pew Research survey conducted in January. In contrast, only 53% thought positively about tech companies and colleges.

A Constant Contact survey released Monday presents a global picture, showing that over 80% of the 1,300 small businesses surveyed in the U.S., Australia, the U.K., and Canada expressed concern about how the economic climate will affect their business this year.