The Urban Institute is out with a new policy brief claiming the individual mandate will only affect 2-5% of the population, and it has managed to get some media traction. The problem is that the whole brief has a huge logical problem by looking at only a tiny window of time. From Urban Institute:

What may be surprising, however, is that if the ACA were in effect today, 94 percent of the total population would not have to newly purchase insurance or pay a fine. While a small number of people would be affected by the individual responsibility requirement, the overall benefit to the population would be large, in terms of reducing premiums and increasing stability of insurance markets.

This is technically true but only if you are looking at a very narrow segment of time, say a one month or one year window.

In real life though, over the course of a person’s adult lifetime their employment, income, and life status are constantly in flux. People lose jobs and/or change jobs all the time. While on any one day only about 5% of the country would be “affected” by the mandate under this briefing’s criteria, over the course of any American’s life time there is a relatively high probability they will eventually be affected.

By analogy, it is true that only a small percentage of Americans would be affected by a change in retirement policy in any one year, but over time it would basically affect every American going forward, since most people plan to retire eventually.

The other problem with this argument is that it assumes people with employer-provided insurance simply aren’t impacted at all. In reality at any moment there is some group of people who are thinking about leaving their job. This possible added expense could affect the decision whether or not to quit and look for a new job. Just because a person is currently exempt from the mandate at this moment doesn’t mean the presence of the mandate and penalty isn’t shaping their possible life choices.