This is enlightening:
More than 80 percent of CEOs and other executives leave money on the table when negotiating. Women have an even greater challenge: Research indicates a backlash effect causes them to hold back.
These findings come from Northwestern University’s Kellogg School of Management, where several professors have closely studied the dynamics women leaders face at the negotiation table.
Research shows that male evaluators penalize female candidates more than male candidates for starting a negotiation.