For advertising sales agents, pay is often based on commissions, not gender, experience or other factors.

Women earned about $49,000 working full-time in 2011, 94 cents to the dollar of their male counterparts.

Part of the pay gap can be attributed to the types of products men and women sell.

For example, selling cars is still a male-dominated business, and those workers tend to earn higher commissions.

NEXT: Pharmacists