The census is out with its annual look at how Americans use the health-care system. You can read the full report here. One of the most interesting findings, though, has to do with how the uninsured use the health-care system. In short, they're using it less than they did a decade ago:

The proportion of adults who saw a medical provider at least once annually fell from 28.4 percent in 2001 to 23.2 percent in 2010. The number of those accessing routine checkups also dropped, from 13.5 percent in 2001 to 11.7 percent in 2010.

It's a bit easier to explain why those with insurance have reduced doctor visits: Numerous surveys show co-pays and cost-sharing in private health plans steadily increasing. 

The uninsured, lacking a health plan, are different: They've tended to foot the entire bill no matter what. What explains their reduction in doctor visits? 

Some of it may have to do with the rising cost of medical care, which continues to grow faster than the rest of the economy. If doctors are charging more, there's a deterrent from turning up in their office. There's some evidence of this when you look at who, among the uninsured, are seeking the most medical services: They tend to be those in poor health, rather than individuals who rate themselves in "excellent" or "good" health. This could suggest that, just like the insured, those without coverage have scaled back on increasingly expensive medical trips.