OPM has been encouraging plans to promote generic drug programs, use of less costly brand-name drugs, mail-order drug programs, and tiered co-payment systems. Even with those efforts, average premiums have risen at or near the double digit range for five straight years-the play year 2003 average increase was 11.1 percent–and earlier this year OPM warned that “health care consultants are again predicting significant health care cost increases next year.” Faced with such increases, enrollees in recent years have been practicing a form of cost containment themselves, by switching to health maintenance organizations and other plans that feature managed care such as lower costs for using in-network providers. Without such switching, the overall average premium increase would be several percentage points higher.