In the past year, the number of women-owned companies has risen by 200,000, translating to a little less than 550 new women-owned firms per day. As of 2012, it's estimated there are more than 8.3 million women-owned businesses in the United States, generating nearly $1.3 trillion in revenues and employing nearly 7.7 million people, according to a new report commissioned by American Express OPEN.

Over the past 15 years, the number of women-owner businesses has surged 54 percent, according to a new report commissioned by American Express OPEN. Employment is up 9 percent and revenues have jumped 58 percent. These rates exceed the growth rates of all but the largest, publicly-traded firms, the study found.

"Even as women-owned firms continue to grow in number at rates exceeding the national average, enterprises at the $250,000 to $499,999 revenue mark are at a turning point in their development," said Susan Sobbott, president of American Express OPEN. "In order to further advance and grow these businesses, new management tools must be implemented."