Question

Consider $200 million of 30-year mortgages with a coupon

of 10 percent paid quarterly. (LG 25-4)

a. What is the quarterly mortgage payment?

b. What are the interest repayments over the first year of life

of the mortgages? What are the principal repayments?

c. Construct a 30-year CMO using this mortgage pool as

collateral. There are three tranches (where A offers the

least protection against prepayment and C offers the

most). A $50 million tranche A makes quarterly pay-

ments of 9 percent; a $100 million tranche B makes

quarterly payments of 10 percent; and a $50 million

tranche C makes quarterly payments of 11 percent.

d. Assuming no amortization of principal and no prepay-

ments, what are the total promised coupon payments to

the three classes? What are the principal payments to

each of the three classes for the first year?

e. If, over the first year, the trustee receives quarterly pre-

payments of $10 million on the mortgage pool, how are

the funds distributed?

f. How can the CMO issuer earn a positive spread on the

CMO?