Three years ago, health economists believed Obamacare’s soon-to-launch marketplaces would grow to replace much of America’s fractured, complex employer-based health insurance system.

Predictions for the employer-sponsored insurance system’s collapse ran rampant. The question around companies shifting workers to the new public marketplaces was often framed not as if but when. University of Pennsylvania’s Zeke Emanuel pegged it at 2025. MIT’s Jonathan Gruber estimated 2050.

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