Massachusetts has, historically, seen health costs rise faster than the rest of the nation. "Health care spending from 2000 to 2004 grew by 7.4 percent in Massachusetts, compared with 6.9 nationally,” write Amy Lischko and Josh Archambault. That's made cost control a key priority in the state. Right after the Massachusetts law passed, premiums in the individual market dropped. This was in contrast to the rest of the country, where health insurance premiums were rising. But in the past two years, Massachusetts has seen individual premiums grow, albeit slightly slower than the rest of the country.
The Great Experiment: The States, The Feds and Your Health Care. Pioneer Institute, 2012.