From Ezra Klein’s article in the Washington Post today:
Back during the health-care reform fight, the Congressional Budget Office looked at the likely effect of adding a public option that paid Medicare rates. “In total, a public plan based on Medicare rates would save $110 billion over 10 years,” the agency concluded. Importantly, the savings would come because premiums would be lower. The basic mechanism here is not complicated: Just as you get better deals by shopping at a mega-retailer like Wal-Mart, you get better deals by working with a mega-insurer like Medicare. Size matters.
As for Ryan’s plan, CBO’s take was just the opposite. “Under the proposal,” they said, “most elderly people would pay more for their health care than they would pay under the current Medicare system.” That is to say, health-care costs go up.