i didn't realize this was news; it's considered a truism in the healthcare insurance industry that you get about 50% turnover every two years. with those kind of numbers, it's in fact to the benefit of the companies that they Do the Right Thing and spend money on disease management programs for patients who will not be members of the same company when the savings or lack of same kick in; quite likely they will be Medicare members.

But that costs money, and as the article points out, employers choose the plan, and they're not as generous in terms of spending extra to provide for the health of employees a long time after they don't work here anymore. So, the market inexorably squeezes the "good" insurers and feeds the "irresponsible" insurers.

But wait; it gets better. As the article briefly alludes to, big companies save money by "self-insuring" their own 'risk'; i.e. the premiums paid and benefits paid out actually go to a company that's a subsidiary of the employer, and the "insurance company" just handles the paperwork for a set fee. Well, legally, the data then belongs to the employer, and doesn't get shared; so that if you work for GE and are insured by BigInsuranceCo but really GE self-insurers and you have a heart attack, then change jobs to GM also insured by BigInsuranceCo but also really self-insured, you are no longer that person who had the heart attack and needs disease management; you're a new person with a clean record.