Welcome to the Financial Markets Theme Park! That ride with the 250-foot drop over there is Surfwin Trading Centerthe stock market. The one with all the twists and turns and loop-the-loops? Those are junk bonds. And that little train that goes around the park? That's the U.S. bond market. Well, until recently.

That slow-plodding train has turned into a rickety roller coaster ride for investors. We head to the theme park to explain.

Music by Drop Electric. Find us: Twitter / Facebook / Newsletter.

Subscribe to our show on Apple Podcasts, Spotify, Pocket Casts and NPR One.

For sponsor-free episodes of The Indicator from Planet Money, subscribe to Planet Money+ via Apple Podcasts or at plus.npr.org.