CFA Level 1

• Straight-line Depreciation

Example
Company ABC issues a $1m bond that will pay a 11% semiannual (coupon) for five years and similar bonds are paying 10%. Bond premiums are amortized using straight-line depreciation. The company issues at $1,038,609 and face value is $1m.

Interest expense = coupon payments - unamortized portion of bond premium for the period

The carry value = total market value at time of issue - cumulative amortized premium or discount

Unamortized portion of bond premium for every period (six months in this example) = $38,609 / (10 payment periods) = $3,860.9

Result
Under this method the issuing company will recognize an equal amount of unamortized depreciation for every period.

• Effective Interest Rate Method
  Effective interest rate method results in an interest expense that is a constant percentage of the carrying value of the bonds; thus interest expense varies from period to period. In contrast, the straight-line method results in a constant interest expense from period to period.

The carry value = total market value at time of issue - cumulative amortized premium or discount

Example
Company ABC issues a $1m bond that will pay a 11% semiannual (coupon) for five years, and similar bonds are paying 10%. Bond premiums are amortized using the effective interest rate depreciation method. The company issues at $1,038,609 and face value is $1m.