It's getting harder to be a woman.

That's the conclusion of a new study on the Global Gender Gap from the World Economic Forum. The annual review looks at 142 countries, and evaluates women's standing in the world based on four indexes: educational attainment, health, political empowerment and economic participation.

The good news: worldwide, men and women are going to school at about the same rate. And women's health outcomes are about as good as the health outcomes of men. But women are not nearly as well represented in government, and the gap in economic participation is only widening. In 74 countries, things have gotten worse since last year. According to the report, “an average gap of 31.7 percent remains to be closed worldwide across the four Index dimensions in order to achieve universal gender parity.”

Closing the economic gap remains the biggest challenge for several reasons. More women than ever are working, but they're still responsible for the bulk of the household chores and caregiving for both children and the elderly. Men do, on average, about 34 percent of the unpaid work that women do. And it's a gap that starts early — girls worldwide spend about 30 percent more of their time on unpaid work. This limits women's ability to earn as much money as men and to grow in their profession, even as they work about an hour longer each day than men do. Female-driven fields also tend to pay less than professions that are dominated by men. “Demographics as well as income and societal expectations therefore play a strong role in the division of labor between women and men when it comes to paid and unpaid work,” the report's authors note.

If things continue at their current rate, it'll take another 170 years to reach gender equity, the authors say. But one bright spot: Based on current trends, the education — specific gender gap could be reduced to parity within the next 10 years. And in some regions of the world, the gender gap is narrowing much faster. South Asia could close its gender gap in 46 years, Europe in 61 years and Latin America in 72 years. The Middle East and North Africa, Central Asia and North America are making the slowest progress.

Though no country has completely closed the gap, the Nordic countries — Iceland, Finland, Norway and Sweden — have made the most progress. Rwanda has also made significant strides in closing its gender gap. It is the only country in the world where more women hold elected office than men. The United States ranks 45th, thanks primarily to two factors: the number of women in the workforce has stagnated in recent years, and women still don't hold nearly as many political positions as men. The country has reached gender parity in education.

Of course, the report's authors note: “None of these forecasts are foregone conclusions. Instead they reflect the current state of progress and serve as a call to action to policymakers and other stakeholders to accelerate gender equality.”