THE map above shows the demographic landscape of the nation's elderly as it is projected to look in 2015, four years after the first Baby Boomers turn sixty-five.

Similarities in the proportions of elderly people in some counties mask differences in the forces that will determine those proportions -- chiefly, in-migration of retirees and out-migration of working-age people. Southern Oregon illustrates both trends: coastal Coos, Curry, and Douglas Counties -- the "Florida of Oregon" -- are expected to continue to attract retirees (mostly Californians), while young job-seekers from the sagebrush country east of the Cascades will keep heading out of state, leaving older folk to "age in place." In West Virginia, the state that boasts the highest proportion of former residents who return after retirement, relocating Baby Boomers are expected to settle primarily in the rural eastern counties, even as younger West Virginians leave the more-industrial western counties.
A combination of out-migration and aging in place is anticipated for most of the rural Great Plains. In terms of percentage, Nebraska's sparsely settled Hooker County could well be the oldest in the heartland come 2015: with its hospital and nursing home set among miles of ranchland, it is projected to have an elderly population exceeding 40 percent.