The same concept applies to an investment by the same name, which has been offered by the Le Conservateur group for 175 years.
Each January 1, a new association tontinière is created for 25 years, bringing together investors.
Those who want a shorter term (but not less than 10 years) can join an existing set-up.
There are versions with one initial investment or with recurring annual or biannual amounts.
When it reaches term, the total is shared. If anyone dies before, their investment is shared among the others.
Tontines offer good rates - 4.54%/year for the most recent to reach term.