According to Labor Department statistics, the number of employed workers 75 and older grew from 669,000 in 1994 to just under 1 million last year. A 2003 survey by the AARP, the nation's largest senior citizens organization, found that 68% of those between the ages of 50 and 70 expected to work past normal retirement age, citing financial need as the primary reason. Many senior citizens are concerned about outliving their retirement savings or facing lower-than-expected investment returns.
See "A New Wrinkle in Workforce", Catherine Saillant, Los Angeles Times, February 23, 2005