This is Planet Money from NPR.

I want to tell you about the moment that I fell in love with economics.

It was around 2008-2009.

I was in college.

I didn't know what I was going to major in.

It was the middle of the financial crisis, so I thought I'll take some econ classes.

In one of these classes, the professor started talking about something kind of unexpected.

She said that economists have been trying to understand why in some parts of the world,

men outnumber women.

They call this the missing women problem.

The most famous example is China with its one child policy, but the missing women problem

shows up in India, in Pakistan, in Taiwan.

And our professor had us read this really interesting paper that had just come out.

It was by this young economist, Nancy Chan, who had this theory.

She thought that the missing women problem was somehow connected to women's incomes.

She realized that in China, picking tea leaves is mostly women's work.

So to test her theory, she came up with this ingenious idea.

She compared regions that grew tea with regions that didn't grow tea.

And she found that in tea growing regions, when the price of tea goes up, all of a sudden

girls were more likely to survive childhood, probably because their mothers were earning

more money and had more say in what family resources were going to their daughters.

This paper blew my mind.

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