Let's first look at how many businesses there are in the U.S.

• There are 27.1 million non-farm businesses in the U.S.
• These businesses generate $30.1 trillion in revenues.

Of those 27.1 million businesses,

• 805,500 are publicly held, with $19.2 trillion in revenues.
• 26,300,000 are privately held, with $11.0 trillion in revenues.

Of the 26.3 million privately held firms, the 441 largest firms employ 6.2 million workers and generate $1.8 trillion.       

Where are the paid employees?

• 5.75 million firms employ 118.7 million individuals who are paid.
• 21.35 million firms do not have paid employees; these are sole proprietorships and partnerships without employees on the payroll.

What kinds of businesses?

• 14.0%  professional, scientific and technical services
• 12.6%  construction
• 11.5%  repair, maintenance, personal, and laundry services 
•  9.9%  retail trade 
•  9.7%  real estate, and rental and leasing
• 42.6%  all other industries

Ownership, Employment & Receipts by Gender in privately held firms:

Women owned   7.8 million non-farm businesses (28.7%)
Women employed  7.6 million persons (6.4% of total employment)
Women’s receipts  $1.2 trillion (3.9% of all receipts)

Men owned     13.9 million non-farm businesses (51.3%)
Men employed   41.5 million persons (35.0% of total employment)
Men’s receipts   $8.5 trillion (28.2% of all receipts)

Equal (*) ownership  4.6 million non-farm businesses (17.0%)
Equal (*) employment 8.1 million persons (6.9% of total employment
Equal (*) receipts  $1.2 trillion (4.2% of all receipts)

(*) Ownership is 50% men and 50% women, eg, equal ownership.

Sources:

U.S. Census Bureau 2007 Survey of Business Owners, released 12/7/2010
Forbes Special Report The Largest Private Companies (In the US in 2008, the 441 largest private companies accounted for $1.8 trillion in revenue and employed 6.2 million people.