Entry-level bankers from Goldman Sachs Group Inc. gathered in a lower Manhattan hotel ballroom last April to listen to the firm’s top executives try to fire them up about their budding careers. David Solomon, co-head of the firm’s investment bank, took on the touchy subject of young employees leaving for private-equity jobs.

“At this time next year, there’s a lot of you in this room who won’t be working at the firm,” he said. “That’s a fact, candidly, we would like to change.”

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