The share of elderly with impairments in their ability to live independently went down between 1% and 1.5% annually between 1984 and 2004, compared to the historical annual decline in chronic disability of 0.6% between 1910 and 1985.

Cutler, David M. 'Are the Benefits of Medicine Worth What We Pay for It? 15th Annual Herbert Lourie Memorial Lecture on Health Policy'.