We're nearing 'peak population.' These economists are worried.

Over the past century, the world's human population has exploded from around 2 billion to 8 billion. Meanwhile, the average fertility rate has gradually declined. And if that trend continues as it has, we may soon see a crash in the population rate, which some argue could have disastrous effects.Today on the show, we talk to co-authors Michael Geruso and Dean Spears about their forthcoming book After the Spike: Population, Progress, and the Case for People. Together, they explain why you should care about declining fertility rates.Related episodes:Babies v climate change; AI v IP; bonds v worldFor sponsor-free episodes of The Indicator from Planet Money, subscribe to Planet Money+ via Apple Podcasts or at plus.npr.org.Fact-checking by Sierra Juarez. Music by Drop Electric. Find us: TikTok, Instagram, Facebook, Newsletter. See pcm.adswizz.com for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences.NPR Privacy Policy