Economy

How much national debt is too much?

Most economic textbooks will tell you that there can be real dangers in running up a big national debt. A major concern is how the debt you add now could slow down economic growth in the future. Economists have not been able to nail down how much debt a country can safely take on. But they have tried.

Back in 2010, two economists took a look at 20 countries over the course of decades, and sometimes centuries, and came back with a number. Their analysis suggested that economic growth slowed significantly once national debt passed 90% of annual GDP... and that is when the fight over debt and growth really took off.

On today's episode: a deep dive on what we know, and what we don't know, about when exactly national debt becomes a problem. We will also try to figure out how worried we should be about the United States' current debt total of 26 trillion dollars.

This episode was hosted by Keith Romer and Nick Fountain. It was produced by Willa Rubin and edited by Molly Messick. It was fact-checked by Sierra Juarez with help from Sofia Shchukina and engineered by Cena Loffredo. Alex Goldmark is Planet Money's executive producer.

Help support Planet Money and hear our bonus episodes by subscribing to Planet Money+
in Apple Podcasts or at plus.npr.org/planetmoney.

Ghost jobs

Today's jobs report shows a slight rise in unemployment to 4%. And some frustrated job seekers are growing tired of applying for job after job with no replies, sometimes asking whether the listings are even real. And this isn't just vexing for applicants. It's also haunting economists when trying to figure out how much slack there is in the labor market, and whether interest rates should be raised or lowered. Today on the show: the rise of ghost jobs. Where they're happening and why.

Related episodes:
Not too hot, not too cold: a 'Goldilocks' jobs report
The Beigie Awards: From Ghosting to Coasting

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

Music by Drop Electric. Find us: TikTok, Instagram, Facebook, Newsletter.

Why California's high speed rail was always going to blow out

99.5 percent of megaprojects are either over time, over budget or have lower benefits than expected. What's going wrong? Today, we look at case studies from California's high speed rail project to the Sydney Opera House to consider the do's and don'ts of ambitious projects.

Bent Flyvbjerg and Dan Gardner's book on megaprojects is How Big Things Get Done: The Surprising Factors that Determine the Fate of Every Project, from Home Renovations to Space Exploration and Everything In Between.

Related episodes:
Why building public transit in the US costs so much (Apple / Spotify)
Planes, trains and bad bridges (Apple / Spotify)

ICYMI, preorder our new Indicator t-shirt at the NPR shop. For more ways to support our show, sign up for Planet Money+ where you'll get sponsor-free listening, bonus episodes, and access to even more Indicator merch!

Music by
Drop Electric. Find us: TikTok, Instagram, Facebook, Newsletter.

Why the U.S. helps pay for Israel's military

The United States has been a supporter of Israel since the nation's establishment in 1948. With the civilian death toll rising in the Israel-Hamas war, growing scrutiny is mounting over just how much the U.S. should support Israel's military. Today, a historical explanation for why the United States tied itself so closely to support for Israel.

Related episodes:
Protesters want schools to divest from Israel. How would that work? (Apple / Spotify)

ICYMI, preorder our new Indicator t-shirt at the NPR shop. For more ways to support our show, sign up for Planet Money+ where you'll get sponsor-free listening, bonus episodes, and access to even more Indicator merch!

Music by
Drop Electric. Find us: TikTok, Instagram, Facebook, Newsletter.

The history of light (classic)

For thousands of years, getting light was a huge hassle. You had to make candles from scratch. This is not as romantic as it sounds. You had to get a cow, raise the cow, feed the cow, kill the cow, get the fat out of the cow, cook the fat, dip wicks into the fat. All that--for not very much light. Now, if we want to light a whole room, we just flip a switch.

The history of light explains why the world today is the way it is. It explains why we aren't all subsistence farmers, and why we can afford to have artists and massage therapists and plumbers. (And, yes, people who make podcasts about the history of light.) The history of light is the history of economic growth--of things getting faster, cheaper, and more efficient.

On today's show: How we got from dim little candles made out of cow fat, to as much light as we want at the flick of a switch.

Today's show was hosted by Jacob Goldstein and David Kestenbaum. It was originally produced by Caitlin Kenney and Damiano Marchetti. Today's rerun was produced by James Sneed, and edited by Jenny Lawton. It was fact-checked by Sierra Juarez. Engineering by Valentina Rodríguez Sánchez. Alex Goldmark is Planet Money's executive producer.

Help support Planet Money and hear our bonus episodes by subscribing to Planet Money+
in Apple Podcasts or at plus.npr.org/planetmoney.