Women have made enormous progress in many arenas, but there is still at least one taboo subject they simply don't talk about enough: money.
Compared to men, women remain far more reluctant to talk about their finances, and it's affecting their saving and investing. A new study released Thursday by Fidelity Investments reports that eight in 10 women have refrained from discussing money with family and friends, partly because the subject is "uncomfortable" or "too personal."
And while 77 percent of the women in the survey said they would be comfortable discussing medical issues on their own with a doctor, just 47 percent said they feel confident when they talk about money and finances with a financial advisor or other financial professional.
What gives? "All the research shows there is a confidence gap for women, even though they have made so much progress in other areas of their lives," said Kathleen Murphy, president of Personal Investing at Fidelity.
Fidelity's research adds weight to other findings about women and girls and their experience with math earlier in their lives. For example, various researchers have found that more girls than boys lose confidence in their math ability and general facility with numbers as early as high school.
Girls even tend to score lower on high school tests such as the AP calculus exam if they have to indicate their gender on the form before taking the exam.
Shelley Correll, a sociology professor at Stanford, has studied gender stereotypes, and she found that male students rate their mathematical ability higher than girls rate theirs, even though a worldwide study of actual math ability found minimal gender differences.
"Girls in elementary school think they are just as good as boys. Something happens in high school," Murphy said. "There is a cultural issue in terms of stereotypes that seem to survive."
That lack of confidence carries into adulthood, studies show. It can affect what women study in college, what careers they pursue and their confidence when it comes to talking about money.
In a 2014 study by Prudential, just 7 percent of women gave themselves an "A" for their knowledge of investing. Men give themselves higher marks, the study noted.
That lack of confidence may contribute to women's reluctance to seek out information on money and investing. Fidelity found that 65 percent of the women in their survey who are offered investment guidance in their workplace do not seek it out. Similarly, Prudential found that 45 percent of the men in their survey seek out market and financial information a few times a month, compared with 26 percent of women.
It's not just older women who lack confidence. Fidelity found in an earlier survey that just 12 percent of millennial women in a couples relationship have a primary role in the investment decisions in their household.
"They're the generation that has graduated more women from college than men and have made the most strides in the workforce," Murphy said. That data is "what I'm most bothered about."
There is a silver lining in the new Fidelity study. Some 92 percent of the respondents said they wanted to learn more about investing, and 83 percent plan to take action this year.
In addition, many women are already demonstrating knowledge of solid investing and saving practices. On average, women save 8.3 percent of their income in tax-deferred accounts such as 401(k)s, compared to a 7.9 percent rate for men, according to another Fidelity study. That study also found that women tend to hold more balanced portfolios than men, which tends to protect them during market turbulence.
Women's retirement portfolios tend to be smaller, since they tend to earn less than men over their lifetime. But Fidelity found that over the past 10 years the women in their study earned essentially the same rate of return with less risk.
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The money challenge facing women is a big one. Some 90 percent of women are likely to be managing their finances on their own at some point, thanks to the prevalence of divorce and women's longer life expectancy. "Women have to take control," Murphy said. But "the study does confirm that women want education, and that's great."