World Bank’s Chief Economist Pinelopi Koujianou Goldberg turned in her resignation on Wednesday, less than two years after taking up the position. Goldberg, a renowned applied microeconomist who has been widely cited for her extensive research on developing countries, joined the World Bank in November 2018 after former chief economist Paul Romer stepped down amidst a controversy about the bank’s statistical methods.

In a letter to colleagues that was obtained by AFP, Goldberg called her resignation a “difficult decision”. She wrote: “This has been a rewarding experience, to work with you on the issues that we care deeply about and ensure that development economics serves to create opportunities for the poor.”

During her tenure at the World Bank, Goldberg worked on the bank’s first trade-focused development report since the late 1980s. The study, published in October 2018, found that despite trade conflicts and technological disruption, global supply and value chains can still boost growth and reduce poverty in developing countries. Some of her other areas of research include the effects of trade on inequality and firm productivity, profits and innovation, and enforcement of intellectual property rights.

Goldberg will officially step down on March 1 and return to teaching at Yale University, where she holds the chair of Elihu Professor of Economics. She will temporarily be replaced by Aart Kraay, director of research in the World Bank’s development research group, while the bank searches for a new chief economist.

In a letter to staff, World Bank president David Malpass praised Goldberg for her intellectual rigor and curiosity, and said she was a “leading intellectual on complex issues facing developing countries”.

“I valued Penny’s intellectual rigor and curiosity,” Malpass said. “In particular, I appreciated Penny’s passion for building the institution’s connection to state-of-the-art academic research and her commitment to drawing young talented economists to the Bank, an effort that will continue beyond her departure.”