(1) Ratable accrual Except as otherwise provided in this subsection, the daily portion of the acquisition discount is an amount equal to
(A) the amount of such discount, divided by
(B) the number of days after the day on which the taxpayer acquired the obligation and up to (and including) the day of its maturity.
(2) Election of accrual on basis of constant interest rate (in lieu of ratable accrual)
(A) In general At the election of the taxpayer with respect to any obligation, the daily portion of the acquisition discount for any day is the portion of the acquisition discount accruing on such day determined (under regulations prescribed by the Secretary) on the basis of
(i) the taxpayers yield to maturity based on the taxpayers cost of acquiring the obligation, and
(ii) compounding daily.
(B) Election irrevocable
An election under subparagraph (A), once made with respect to any obligation, shall be irrevocable.