Name the parts of a US Treasury coupon bond and contrast it with Treasury STRIPS, taking in how P-STRIPS and C-STRIPS differ.
The idea
A US Treasury coupon note or bond has a par (face) value repaid at maturity, a stated annual coupon rate, a maturity date, and coupons paid every six months. Each coupon is calculated as Coupon = coupon rate × par ÷ 2, which is half the annual amount. Notes mature in 2 to 10 years and bonds beyond that. Treasury STRIPS are zero-coupon securities that exist because a coupon security is separated into its individual cash flows, each of which then trades alone. A C-STRIP comes from a coupon payment and a P-STRIP from the principal payment. On the maturity date the final coupon becomes a C-STRIP and the principal a P-STRIP, and the two can trade at slightly different prices. A STRIP's duration equals its maturity, which is longer than the duration of a coupon bond of the same maturity. The exam favours counting the pieces and telling the two kinds apart.
Formulas
Semiannual coupon on a US Treasury note or bond
Coupon = c × F ÷ 2
- c
- the stated annual coupon rate
- F
- the par (face) value
Treasury coupons are paid every six months, so the stated annual rate is halved. Using the full annual rate doubles the payment.
A practice question
A US Treasury note has a face value of USD 100,000 and a coupon rate of 4.5%. Each coupon payment is:
- USD 2,250 - correct
- USD 4,500Why not: Pays the whole annual coupon at each date instead of half, since Treasuries pay semiannually.
- USD 1,125Why not: Divides by four, as for a quarterly payer.
- USD 2,225Why not: Converts 4.5% to an equivalent semiannual rate, 1.045^0.5 - 1, rather than splitting the stated rate in half.
A Treasury coupon is coupon rate x par / 2 = 0.045 x 100,000 / 2 = 2,250. The stated rate is simply halved.
A harder one
A dealer strips USD 10 million face value of a newly issued 5-year Treasury note with a 6% coupon. Which STRIPS pay on the maturity date?
- One C-STRIP paying USD 10.3 millionWhy not: Merges the final coupon and principal into one coupon strip.
- One P-STRIP paying USD 10.3 millionWhy not: Merges the final coupon and principal into one principal strip.
- A P-STRIP paying USD 10 million and a C-STRIP paying USD 0.3 million - correct
- A C-STRIP paying USD 10 million and a P-STRIP paying USD 0.3 millionWhy not: Swaps the labels, assigning the principal to the C-STRIP and the coupon to the P-STRIP.
The final semiannual coupon is 0.06 x 10 / 2 = 0.3 million, which becomes a C-STRIP; the 10 million principal becomes a P-STRIP. They pay on the same date.
The hardest tier
A three-year C-STRIP trades at 91.00 per 100 face value. Its semiannually compounded yield is closest to:
- 3.30%Why not: Uses simple interest, (100 / 91 - 1) / 3, with no compounding.
- 3.17% - correct
- 6.39%Why not: Takes the three-year root and doubles it, treating three years as three half-year periods.
- 1.58%Why not: Uses six half-year periods but forgets to double the periodic rate to annualise it.
A zero compounds over six half-years: 91 x (1 + y/2)^6 = 100, so y = 2 x ((100 / 91)^(1/6) - 1) = 2 x 0.01584 = 3.17%.
In the app: 6 practice questions on this outcome, spaced review that brings it back before you forget it.
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