Editor's note: The following is part of a series of stories that take a deep dive into the demographics and firmographics of small and midsize businesses in the United States. The findings are derived from surveys distributed from November 2010 to January 2011 to 2,223 owners of businesses with less than 500 employees.

Growth of women-owned businesses in the United States is far outpacing that of businesses on the whole—but what type of companies are they running, what degree of success are they having and who are the women managing these firms?

As part of its research into how U.S. small and midsize businesses are doing, American City Business Journals (the parent company of Portfolio.com) wanted to find out the answers to all of those questions. Godfrey Phillips, ACBJ's vice president for research, guided us through some of the findings from the last study he conducted with lead strategist Jessie Shaw.

Among the survey's key findings: Women-owned companies are the fastest-growing segment of the business market, and the places where this is clearest are in the smallest U.S. companies. Women run smaller, younger companies. They're independent decisionmakers. They're younger and less upscale than their male counterparts. And they travel and work less, yet find themselves more personally stressed and time crunched.

Click Next for insight concerning the type of women that own businesses, how many employees they typically employ, where they run their businesses and more.