The idea is you give up return of principal for a bet on the NPV of coupons during your life. Which is a gamble, and quite tidy too: nothing to leave to one's h

The idea is you give up return of principal for a bet on the NPV of coupons during your life. Which is a gamble, and quite tidy too: nothing to leave to one's heirs for all but one of the participants[1]. But also a gamble on a particular pool of assets. "At retirement, you and a bunch of other people each chip in $20,000 to buy a ton of mutual funds or stocks or whatever." But these "whatevers" are volatile assets that will produce losses in some years--the opposite of the usual advice to lower volatile asset holdings at retirement. So now it's a double bet: first on NPV/longevity, and second on the health of the underlying assets. Exactly the kind of thing that Wall St would love to sell to the public. [1] All of the underlying assets being transferred to the last survivor is one type of tontine; in another, certain to be a favorite of Wall St., the underlying would be transferred to the plan manager after the death of the last participant.