The caveat: Next year won't be another record-setter. Aon's data indicates the 2014 rate increase will be around 6 or 7 percent, as the economy continues to rebound and new costs associated with health care reform are absorbed into the corporate plan system.

In a related matter, the analysis discovered that average employee out-of-pocket costs (co-payments, co-insurance and deductibles) increased 12.8 percent in 2013, compared to just 6.2 percent in 2012, as employers continued to insist that employees share coverage responsibility.

Despite the outlook for a large hike next year, the bottom line is that employers are taking control of health insurance rather than shrugging their shoulders and pretending the line item doesn't exist.

"Health care remains a top priority for U.S. employers, and most are taking action to prepare for increasing cost, risk and change," said Jim Winkler, chief innovation officer for the U.S. Health & Benefits practice at Aon Hewitt.

"As the health care industry continues to evolve, employers realize that a traditional 'managed trend' approach will be less effective in mitigating cost increases over time. Instead, they are exploring innovative new delivery approaches, requiring participants to take a more active role in their own health care planning, and holding health care providers more accountable to reduce unnecessary expenses and create more efficiency in the way health care is purchased."

These kinds of measures were referred to as "pockets of promising innovation in the health care industry" by Tim Nimmer, chief health care actuary at Aon Hewitt. While this trend will continue, Nimmer noted that most of the slowing of premiums rates can be attributed to less exciting factors: "the lagged effect from the economic recession on health care spending and continued adjustments as employers and insurers phase out the conservatism that was reflected in earlier premiums due to uncertainty around economic conditions and health care reform."

Aon's analysis showed that 72 percent of employers say they focus their health care strategy nowadays "primarily on programs that improve health risk and reduce medical costs."

That includes a shift away from HMOs. The data showed that HMO premium increases outpace the alternatives. HMO premiums will rise 7.5 percent in 2014 compared to 6.5 percent for both preferred provider organization plans and point-of-service plans.

Also, employers are increasingly examining the emerging private health exchanges because they offer more choice to employees, reduce administration costs to the company, and promise overall lower costs going forward.

The analysis suggests that "about 28 percent plan to move into a private health care exchange over the next three-to-five years."

Aon's own private exchange already boasts 18 employer clients, including Walgreens, Sears and Darden Restaurants.

When it comes to plan design changes, Aon's research again offers bad news for HMOs. Aon reports that "consumer-driven health plans have surpassed health maintenance organizations as the second-most popular plan option offered by employers. A growing number of employers are offering CDHPs as the only plan option. While just 10 percent of companies do so today, another 44 percent are considering it in the next three to five years."

When it comes to who is eligible for coverage under the company plan, many employers are ratcheting back on the old generosity. Specific actions being taken include:

• Reducing the employer subsidy for covered dependents. Aon Hewitt's research shows that 54 percent of employers are considering reducing subsidies across all dependent tiers in the next three to five years.
• Implementing or increasing surcharges for adult dependents with access to coverage elsewhere. Aon Hewitt's research shows 69 percent of employers have implemented or plan to implement surcharges for adult dependents.
• Adopting a unitized pricing approach, where employers charge per dependent. While just 4 percent of employers currently adopt this approach, another 47 percent are considering it in the future.
• Assessing the eligibility of covered dependents in their plans. A recent Aon Hewitt survey shows that two-thirds of employers have completed a program audit of covered dependents to ensure only those who are eligible will remain on the plan.

Increased cost sharing, as mentioned above, is drawing more employer attention. "The amount of money employees will need to contribute out of their paychecks — both in premiums and out-of-pocket costs — is continuing to climb," Aon said. "Today, employees' share of the overall health care premium is 22 percent, compared to just 18.6 percent a decade ago. 

"Additionally, Aon Hewitt's research shows that 47 percent of employers have increased participants' deductibles and/or copays in the past year, and another 43 percent are considering doing so in the next three to five years."