40 ILCS 5/7-119

"Annuity": A series of equal monthly payments, payable as of the first day of each calendar month during the life of an annuitant, the first payment to be made as of the first day of the calendar month coincidental with or next following the date upon which the annuity begins, and the last payment to be made as of the first day of the calendar month in which the annuitant dies or the annuity is terminated.