A friend writes:

In yesterday’s New York Times, Eduardo Porter points out some surprising features of Social Security benefits, based on calculations by Eugene Steuerle and his colleagues at the Urban Institute. For example, women earn a rate of return that is about 50 percent higher than men with the same earnings history White males earn a higher rate of return than black males, and male college graduates do better than high school dropouts.
Steuerle reports on even more usual (and unfair) results in his study of the treatment of spouses.
Tom Saving and Larry Kotlikoff have done similar rate of return studies. Also, Kotlikoff finds, contrary to Porter’s reporting – that the system is overall regressive – imposing a higher lifetime tax on middle- and lower- income workers that is higher than for high income workers.
In most personal retirement account proposals people with the same investments would earn the same rate of return – regardless of race, sex, education, etc. With earnings sharing, spouses would be equal partners with their husbands in PRA contributions.