This week, we're running some of our favorite episodes from the past year.

This episode digs into why reading glasses are so available in the U.S.

And yet, why so many people around the world are living without them.

NPR.

It's one of those annoying facts of life that the older you get, the more often you find that your body just doesn't work like it used to.

Case in point, I'm almost 40 years old. And for the past year or so, I find that just reading things has become more difficult. Like, I find myself squinting to read an article on my computer or just, like,

constantly enlarging the font. And I know that this is only going to get worse in the coming

years. And the fact of this would be personally and professionally devastating if the solution were not extremely easy and cheap to come by.

Reading glasses.

Right?

I can get reading glasses at any pharmacy or convenience store for just a few bucks.

Online, I could get five pairs of reading glasses for a little

more than a dollar apiece. And that's why I was super surprised to learn this statistic. According to a

report by the Lancet Global Health Commission, the number of people who have unaddressed vision

loss that could be solved with a simple pair of reading glasses is around 510 million.

That is more than the populations of the U.S., Mexico, and Canada combined.

So if reading glasses are so available and cheap here in the U.S., why are so many people around the world living without them?

This is the indicator for Planet Money.

I'm Adrienne Ma.

And today on the show, we'll answer that question.

And we'll learn the economic solution to this reading glasses shortage.

This message comes from Wise, the app for doing things in other currencies.

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