Melinda and Bill Gates Reuters Pool Photo taken at Elysee Palace in Paris, France on April 21, 2017.

For over a decade, researchers have known that everything changes in almost every community and country worldwide when women have money.

On Monday Melinda Gates published an op-ed in Quartz in which she and husband Bill Gates announced a four-year pledge of $170 million to help empower women economically worldwide.

The decision comes at a time when 1) the Gates Foundation has tried to block the damage levied at poor women worldwide by cuts In the US budget that funds global women's health initiatives -- not abortions, but 'yes' to birth control being available at women's health clinics. Generally-speaking, the Trump administration stands opposed to taxpayer-funded birth control, arguing that it diminishes religious freedoms for those Americans opposed to contraception; and 2) in response to #MeToo stories and the prevalence of sexual harassment and violence against women worldwide.

The money, from the Bill & Melinda Gates Foundation, will be spent over four years “to help women exercise their economic power,” Melinda Gates wrote. She noted that research shows economic power is the “most promising entry points for gender equality.”

“Simply put when money flows into the hands of women who have the authority to use it, everything changes,” Melinda Gates wrote.

We’ve been investing in women’s health for a long time and seen significant progress. But as I spend more time visiting communities and meeting people around the world, I am convinced that we’ll never reach our goals if we don’t also address the systematic way that women and girls are undervalued. With a new focus on women’s economic empowerment, connecting women to markets, making sure they have access to financial services, and empowering them to help themselves, we aim to help tear down the barriers that keep half the world from leading a full life.

Less than 10% of India’s land is owned by women. Image via impatientoptimists.org, a blog of the Gates Foundation

According to the op-ed, the donation will fund a three-pronged approach to women's economic empowerment: First, the Bill & Melinda Gates Foundation will support and organize female farmers so they can sell their products at competitive prices; Second, the foundation will work in eight countries, including India, Pakistan and Tanzania, to promote women using digital bank accounts; And lastly, the foundation will facilitate self-help groups allowing women and girls share information about “everything from launching a small business to raising healthy children.”

Gates explains what we know about how women’s economic empowerment is key to gender equality, saying families benefit when women control household finances.

“Research shows ... that women are much more likely than men to buy things that set their families on a pathway out of poverty, like nutritious food, health care, and education,” Gates wrote. Additionally, Gates noted, when women have economic power, communities begin to rethink the roles women play in society.

First, their families benefit. One in three married women in the poorest countries have no say over major household purchases. Research shows, however, that women are much more likely than men to buy things that set their families on a pathway out of poverty, like nutritious food, health care, and education. In Niger, for example, when women had more financial autonomy, their families ate more meat and fish. One of the most astonishing statistics I’ve seen is that when a mother has control over her family’s money, her children are 20% more likely to survive.

Second, everyone starts to re-think the part women can play in their own communities. A recent study in India found that merely owning and using a bank account led women to work outside the home more. As a result, they earned more money, but they also changed men’s perception of them. By defying a social norm that confined them inside, they started to change it.

“Women acting on their own can do what all the philanthropic organizations in the world can never accomplish: change the unwritten rule that women are lesser than men,” Gates concludes. “Our role, as we see it, is to make targeted investments that give women the opportunity to write new rules.”

Related: Women farmers work hard but get a raw deal Impatient Optimists