Summary Box: Overhaul gives insurers growth chance

GROWTH SPURT: The health care overhaul's insurance exchanges may help as many as 12 million people find coverage in 2014, according to health care consultant PwC. That equals $55 billion in premiums for insurers. Those totals may rise to 29 million people and $205 billion in premiums by 2021.

WHY THIS MATTERS: The exchanges represent a key source of growth to private health insurers that have struggled at times to increase their enrollment in a tough economy.

A CONDITION: PwC says growth may vary depending on whether states expand their Medicaid programs, which provide coverage for the needy and disabled.