The Washington Post's Wonkblog has discovered to its surprise that, contrary to what some people have been telling them, demographics is by far the most important factor in explaining the increase in the number of Social Security disability claims. Wonkblog concedes that this simple, straightforward explanation might have some merit but they can't believe that's all there is to it. I would suggest that Wonkblog take a look at Steve Goss' recent testimony before a Congressional committee. He's Social Security's Chief Actuary. The whole subject of disability incidence rate is extremely complicated but the bottom line is that a lot of what passes for increases in disability incidence is actually comparisons of peaks and valleys. Look at the long term and it becomes obvious that the only real problem is a long anticipated need for additional funding for the Disability Trust Fund caused by the aging of the baby boom population.