An interest-only strip (IO) receives a pool’s interest payments and a principal-only strip (PO) its principal payments, scheduled and prepaid; together they are the pool.
Exemplos
Example 12.9 (Splitting the pool)
At its option-adjusted spread the pool splits into an IO worth 25.26 and a PO worth 74.74. When rates rise 25 basis points the IO gains (26.61) and the PO loses (72.10): slower prepayment extends the interest stream and delays the principal. The IO is a rare asset with negative duration (Figure 12.2).