Megan McArdle is still on the case of the mysterious numbers inside the recent RAND study on who’s enrolled and who isn’t:

OK, so why is this puzzling? Well, umm, what’s all that employer-sponsored insurance doing there? Why did so many people with “other” insurance lose it? There is nothing in Obamacare that should have caused either outcome; the employer mandate hasn’t even taken effect.

I mean, I could tell a story about how the exchanges make a trivial contribution to solving the problem of the uninsured, but a lot of uninsured people who are afraid of the individual mandate bite the bullet and sign up for that employer-sponsored insurance they’ve been declining because their share of the premium is $150 a month. Where the existence of the exchanges causes a lot of companies to dump their retirees onto the individual market in order to pick up some subsidies. Where people who already had individual policies take one look at the new premiums they have to pay and decide it’s better to just sign up for their spouse’s insurance, even if they have to pay the whole premium for the additional coverage. It’s not a particularly flattering story for Obamacare, but it’s a story you can string together from these data.

A riddle wrapped in a media fog inside a stonewalling Administration.