Young women are still less likely to negotiate a job offer. Why?

Nearly a decade ago, Carnegie Mellon University researchers surveyed a group of graduating college students and found just 7 percent of women said they'd tried to negotiate their initial job offers, compared to a whopping 57 percent of men.

This negotiation gap appears to stubbornly persist among today's young workers — though it's less dramatic. The latest evidence comes from Earnest, a lending company in San Francisco, which recently asked 1,005 Americans nationwide, age 18 to 44, about their approach to conversations about pay. Forty-two percent of men in the report's youngest age group, 18 to 24, reported asking for more money, compared to just 26 percent of their female peers.

The chasm appears to close with age, at least in these data: Forty-three percent of women, ages 25 to 34, said they negotiated a job offer, compared to only 35 percent of their male counterparts:

Negotiations, of course, don't always yield favorable results. In Earnest's 18-to-24 group, the men were more likely to have a "successful" negotiation compared to women, by a margin of 24 percent to 16 percent. In the 25-to-34 group, women were more likely to successfully bargain. Older men and women had about the same odds.

No matter the experience level, firms apparently shut down workers left and right:

Overall, the data show that it's young women, perhaps in their first or second job, who shy away most from the negotiation process — a perplexing revelation, considering women are outpacing men in college enrollment and degree attainment.

So, what's going on?

The Earnest survey didn't elaborate on the meaning of "negotiate." So, the women in the older age brackets may have found more success in asking for benefits like flexible schedules, rather than simply higher salaries.

More generally, women who opt out of negotiating aren't succumbing to some confidence problem, notes Hannah Riley Bowles, a Harvard lecturer who studies gender in negotiation. They might be more accurately reading the social climate. They might see it's just not a good idea.

"The answer has more to do with how women are treated when they negotiate than it has to do with their general confidence or skills at negotiation," Bowles wrote recently in the Harvard Business Review. "Their reticence is based on an accurate read of the social environment. Women get a nervous feeling about negotiating for higher pay because they are intuiting — correctly — that self-advocating for higher pay would present a socially difficult situation for them — more so than for men."

In three 2006 experiments, subjects of both sexes were asked to think like hiring managers and evaluate mock job negotiations. They penalized women more than men for making extra demands. That happened whether they watched women negotiate on video or read about their efforts on paper. People found men who negotiated to be generally more persuasive, even if they followed the same script as female hopefuls. (Bowles and her colleagues theorize this may have something to do with an unspoken social norm that women are expected to be team players and men are supposed to be bold leaders.)

An April study from the Harvard Business School and Stanford University, meanwhile, found that always opting to negotiate a job offer, regardless of the circumstances, might actually backfire.

Researchers set up an experiment in which people playing “workers” and “firms” entered wage-setting discussions. They forced some women to negotiate every offer and gave others the choice to either accept the initial package or push for more. When women were forced to negotiate, their overall wages actually dropped. The rate by which final wages fell below the initial offer increased from 9 percent, when women chose whether to negotiate, to 33 percent.

“In light of such complexities,” the authors wrote, “women may be good judges of whether or not they should lean in.”