Small employers also have less flexibility to tinker with plan design. They're most likely to shop around for a cheaper plan.

In New York, where providers operate very independently and generally belong to a number of overlapping managed care networks, average cost is a whopping $4,743 per employee. But in Los Angeles, another big and expensive city, HMOs are very effective, and cost is only $3,375.

It's too early to tell whether the decline in HMO/POS enrollment is a short-term phenomenon or -- more ominously -- a sign that these managed care plans may not become the centerpiece of the nation's health care delivery system after all.

The one-time cost reduction employers experience as their workers move into less expensive plans has been masking the underlying cost trend. Migration out of indemnity plans slowed to a trickle last year, so we're finally seeing real trend reflected in the national cost figures.

We used to think of cost-shifting as something you could do only every so often. But we're seeing a new willingness on the part of employers — born of desperation — to shift cost in successive years to achieve acceptable cost increases.

Employees are bearing more of the costs because double-digit increases are unsustainable.