Photographer: Andrew Harrer/Bloomberg
Photographer: Andrew Harrer/Bloomberg

Amid the hubbub over yesterday’s embarrassingly low initial enrollment numbers for the Affordable Care Act, it’s worth remembering those numbers are useful for one thing only: hinting at whether the law will perform as advertised. As it turns out, the numbers provide little hint about anything.

Certainly, what figures the report contains are disheartening. From Oct. 1 through Nov. 2, only 106,000 people selected a health insurance plan through the state exchanges created under Obamacare, about a fifth as many as the government had projected. And that includes an unspecified number of people who have yet to pay a single dollar, some of whom may change their minds.

The report also offers something for glass-half-full types, who will note that when Medicaid enrollment is added in, half a million people signed up for health insurance last month. Compared with a world without Obamacare, that’s cause for celebration.

This week’s figures are especially telling for what they don’t include, however. The success of the exchanges will depend as much on which people enroll as on how many, because the ultimate cost of insurance will be determined by the balance of the young and healthy and the old and sick who sign on. Too many high-cost enrollees will drive up premiums, and with them the price tag for taxpayers.

Yet the report is silent on the ages of enrollees and on whether the age distribution matches the assumptions that drove the law’s initial cost projections.

It also ignores a second important measurement: whether the government-touted week-over-week improvements in the operation of HealthCare.gov are leading to a week-over-week increase in enrollment. The number of people who signed up during October probably matters less than whether, and how quickly, that number is increasing.

The result is a set of figures that tell us what we already knew: Not many people have signed up for Obamacare so far. That’s fine for critics of the law, who are already using the disappointing report to predict, again, its imminent collapse. But the scant data should trouble Obamacare’s supporters.

If the government doesn’t know the age distribution of enrollees or the pace of signups, that could mean a problem for the law. And if it knows but won’t say, it suggests, even worse, that the trends aren’t good.

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