Some of the nation's top health insurers recently revealed that they were doing quite well -- even as the rest of the economy struggles.

UnitedHealth, for instance, posted more than $25 billion in revenue between July and September -- and profits of more than $1 billion. In the Pittsburgh area, the largest insurer, Highmark Blue Cross/Blue Shield, posted $462 million in profits last year -- an increase of 146 percent.

Ordinary Americans are understandably wondering if their steadily increasing premiums are simply lining insurers' pockets. Insurers are doing nothing to dissuade them of that notion by refusing to make public the data they use to justify their rate hikes.

That's unacceptable. Consumers have a right to know how insurers are setting their premiums. Armed with such data, they would be better positioned not just to resist unreasonable premium increases but also to make more informed and cost-effective health care decisions.

For many health insurers, business has never been so good. 2010 marked the third straight year of record profits.

Not coincidentally, premiums have also been rising steadily. They were up 9 percent in 2011, after increases of 3 percent in 2010 and 5 percent in 2009.

And last month, the Pennsylvania Department of Insurance green-lit a 9.9-percent increase for three Highmark plans next year.

Today, roughly 10 percent of workers covered by their employer have a deductible of at least $2,000. That's up from just 5 percent of workers in 2008.

Rising premiums aren't just crushing employees. At a time of profound economic uncertainty, the average employer will have to deal with a 7-percent increase in the cost of health coverage.

It's perfectly reasonable to connect rising premiums to rising insurance-industry profits.

Insurers insist that the high cost of care is to blame for the high cost of coverage. That seems plausible. But why won't they open up their books to prove it?

Such information would be particularly consequential in the recent conflict between UPMC, the region's 20-hospital network, and Highmark over renewing the service agreement between the two health-care giants.

Although ostensibly nonprofits, both are swimming in cash. Highmark's reserves are near $4 billion, while UPMC's investment reserves stand at $3.3 billion.

Both have publicly sung the praises of data transparency -- but neither is rushing to peel back the curtain on prices.

In 2010, for instance, Highmark claimed that opaque policies that bundled prescription and medical benefits could save employers money on their benefits. Not surprising -- that's what Highmark sells.

But research from consulting firm Mercer shows that carved-out pharmacy benefits can help employers trim their prescription-drug spending by up to 20 percent. Because electronic prescription data are available as soon as a patient leaves the pharmacy, they can offer employers crucial insights that they can use to construct supplemental health-enhancing offerings like medical interventions, disease management and wellness programs.

Insurers -- particularly those like Highmark that have virtual monopolies -- have less incentive to implement such money-saving programs. After all, their customers have few alternatives.

Insurers argue that their data is a proprietary "trade secret" and that publicizing this information would benefit their rivals, reduce competition, and thereby lead to higher prices.

But if consumers had access to insurers' data, they'd be able to determine where their health-care dollars were going -- and take steps to cut costs .

For instance, if employers learned that pricey doctors' visits were driving up the cost of their coverage, they could consider establishing on-site medical clinics to help save money.

Or if companies found out that prescription drugs were to blame for insurers' rate hikes, they could encourage their employees to switch to cheaper generic alternatives.

Employers and employees alike would benefit. Health costs for both would plummet even as beneficiaries received equally good or better care.

Only insurers would be left out in the cold. But is it really regulators' job to protect insurers' huge profit margins?

The public has a right to know why their premiums are going up so fast and to take action if insurers are indeed putting their health in jeopardy to juice profits.

Data transparency can empower consumers to fight back against a health insurance industry that appears disinterested in actually delivering care.