http://www.washingtonpost.com/wp-dyn/content/article/2010/12/17/AR2010121702366.html?hpid=news-col-blogA summary of how Massachusetts is doing under Romneycare (bold emphasis mine):
This week, the state's health and human services agency released the results of a new, independent survey examining coverage in Massachusetts. More than 98 percent - 98 percent! - of the state's residents now have health insurance, as do more than 99 percent of the state's children.
Remarkably, those numbers have gotten better in recent years, with the number of uninsured residents in the state falling to 1.9 percent in 2010 from 2.6 percent in 2008. That's very unusual. Normally, the ranks of the uninsured swell during recessions as people lose their jobs and states cut back on public programs to balance their budgets. Nationally, the number of Americans who are uninsured rose to 16.76 percent in 2010 from 14.8 percent in 2008, according to Gallup.
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Like the federal law, the Massachusetts law left most people's health arrangements alone. The exception: people who don't get their coverage through a large employer or a public program. That accounts for most of the uninsured. It's also where the individual mandate is primarily in play and where the "exchanges" - the purchasing markets that put individuals and small businesses in a single pool and force insurers to compete for their business and treat them fairly - really matter.
In Massachusetts, that market has worked better than expected. According to data from America's Health Insurance Plans, the largest health insurer trade group, premiums for that market have fallen by 40 percent since the reforms were put in place. Nationally, those premiums have risen by 14 percent.