65 pages. "[GAO was asked] to address [1] how to define and describe 'progressivity,' that is, the distribution of benefits and taxes with respect to earnings level, when assessing the current Social Security system or proposed changes to it; [2] what factors influence the distributional effects of the current Social Security program; and [3] what would be the distributional effects of various reform proposals, compared with alternative solvent baselines for the current system." [GAO-04-747, Jun. 15, 2004]