The Boston College Center for Retirement Studies has published a research paper entitled "Financing Disability Benefits in a System of Individual Accounts: Lessons From International Experience." The study indicates that there are three predominate methods for dealing with disability benefits when private accounts are carved out of a Social Security system:
1. The Chilean Model, under which the capital in a newly disabled individual’s account is augmented by additional capital provided by a private insurer, such that the combined account balance is sufficient to finance a lifetime defined benefit stream prescribed by law.
2. The Swedish Model, under which government-financed disability benefits are paid up to a particular cut-off age (e.g. the retirement age, or an age close to the retirement age), and, in addition, the government finances contributions to each disabled individual’s account. Upon reaching the cut-off age, the disability benefit ceases, and the assets of the individual account are used to finance a stream of retirement income. A disabled individual’s replacement rate may increase or decrease upon reaching the retirement age, because disability benefits are defined by a formula, while old age benefits are a function of interest rates and mortality rates.
3. The Hungarian Model, under which the assets of a newly disabled person’s individual account are transferred to the PAYG system, and, in return, the PAYG system finances a lifetime defined benefit stream.