NPR.

This is the indicator from Planet Money, I'm Darian Woods.

And I'm Paddy Hirsch.

The butterfly effect is what happens when a small change in one part of a system can eventually

trigger a much larger disruption in the same system.

You know, a butterfly twitches its wings and Dublin, and a few weeks later, Australia

is struck by a tornado.

But you know, right now, the finance world has its collective eye on one particular butterfly

in Tokyo.

And it's wondering when that butterfly beats its wings, how bad the repercussions might

be.

The butterfly is the interest rate on the Japanese 10-year government bond, which has been

locked in a narrow range since 2016.

That range lock is called the Yield Curve Control, and the global bond market is a buzz

with speculation that the Japanese central bank could remove or adjust it.

On today's show, we're going to look at Japan's Yield Curve Control to explain what it is

and why it exists.

And also what might happen if it goes away.

There are literally billions of dollars at stake on this one.

We'll find out more after the break.

When we talk about government bond markets, we tend to focus on the US.

That's because America's bond market is so large and it's bonds are in such demand.

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