DUBLIN, Ohio – Suffice it to say, it was an “aha” moment. All that was missing was the veritable lightbulb going off.

The rest—108 at the end of 2023—have been stuck in “the middle-income trap. Since 1970, the median income per capita of middle-income countries has never risen above 10 percent of the US level.

Audience editors: Samantha Cooney, Annabel Gutterman, Soo Jin Kim, Kitty Ruskin, Kari Sonde, Kimberly Tal, and Meg Zukin Designer: Rich Morgan Digital producer: Juwayriah Wright Editors: Emma ...