There is one problem with that. People can predict their own life expectancy. People who expect to live shorter will avoid such scheme.
To give an example: state pension in my (European) country is unfair to men. We live shorter and retire latter. In average women gets 45% more money for the same contribution. As result men are avoiding state pension and use private funds.
To give an example: state pension in my (European) country is unfair to men. We live shorter and retire latter. In average women gets 45% more money for the same contribution. As result men are avoiding state pension and use private funds.