In an article on the release of the 2012 Social Security trustees report the Washington Post told readers that:
"Social Security’s bleak outlook is primarily driven by the ever-larger numbers of people in the baby boom generation entering retirement."
Actually the fact that baby boomers would enter retirement is not news. Back in 1983, the Greenspan Commission knew that the baby boomers would retire, yet they still projected that the program would be able to pay all promised benefits into the 2050s.
The main reason that the program's finances have deteriorated relative to the projected path is that wage growth has not kept pace with the path projected. This is in part due to the fact that productivity growth slowed in the 80s, before accelerating again in the mid-90s and in part due to the fact that much more wage income now goes to people earning above the taxable cap.
In 1983 only 10 percent of wage income fell above the cap and escaped taxation. Now more than 18 percent of wage income is above the cap.