31 percent of YHI buyers were in 55-64 age bracket

BOISE, Idaho (AP) -- Older people made up the biggest share of residents purchasing health coverage via Idaho's insurance exchange, with 31 percent of the 19,922 buyers through December between 55 and 64.

Still, Your Health Idaho officials announced Monday the coveted younger generation between 18 and 34 — the "young invincibles" being counted on to make exchanges across America work — accounted for 24 percent of enrollees.

Older, sicker residents were expected to be significant consumers, since they're likely to avail themselves of benefits.

But President Barack Obama and exchange officials want as many younger, healthy enrollees as possible, to offset costs of covering older ones.

Monday's report offered the most detail yet about people buying policies via Idaho's online marketplace, one of the exchanges critical to President Obama's plan to expand coverage.