(CNN) The New York Times Editorial Board called for South Bend, Indiana, Mayor Pete Buttigieg to disclose his clients from his time at McKinsey, a management consulting firm, in an opinion piece published Thursday evening.

The board wrote in the editorial, "Mr. Buttigieg owes voters a more complete account of his time at the company" than the limited information he's provided while campaigning for the Democratic nomination for president.

Buttigieg, who worked for the consulting firm from 2007 to 2010, signed a nondisclosure agreement covering his time at the company. He told reporters in September that he had joined McKinsey because "I felt that I need to get experience in business."

"I had studied economics academically ... and I had worked a little bit around campaigns, but I hadn't done the work of being involved in how people and money and goods move around the world," Buttigieg told CNN. "And I had an opportunity to work on those things at a place known for being very strong at it ... it felt like the missing piece of my education."

On Tuesday, the Times reported that McKinsey consulted with Immigrations and Custom Enforcement on "detention savings opportunities," including cutting spending on food and medical care for detained migrants, as part of a $20 million contract with ICE.

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