Programmed monthly or quarterly withdrawals calculated on the basis of an expected life span;

Annuity for life purchased from a life insurance company licensed by the National Insurance Commission with monthly or quarterly payments; and

A lump sum from the balance standing to the credit of his retirement savings account: provided that the amount left after that lump sum withdrawal shall be sufficient to procure an annuity or fund programmed withdrawals that will produce an amount not less than 50 per cent of his annual remuneration as at the date of his retirement.