What are short duration bonds?
A short duration bond is generally a bond with a short time to maturity. At AXA IM we define this period as 5 years or less. Short-term bonds generally carry less uncertainty because the principal is repaid more quickly and can be reinvested earlier. However, duration is more than just term to maturity.
Maturity versus duration
Maturity is simply the number of years left until the bond’s principal is repaid. Duration takes maturity into account but also bond coupon rates and yield. When coupons are included, the bond's duration number (in years) will always be less than the maturity number. Generally, bonds with shorter maturities or higher coupons will have shorter durations.
What does duration indicate?
Duration is considered an indicator of one of the key risks in fixed income investing – interest rate risk. The calculation of duration essentially measures how sensitive the value of future cash flows is to changes in interest rates. The shorter a bond’s duration, the less the bond’s price will change when interest rates move, thus short duration bonds are less exposed to interest rate risk.
Why is duration useful?
Duration is an extremely useful tool in helping to manage fixed income portfolio risk. First, it allows the portfolio manager to compare the risk sensitivity and potential price volatility of bonds with differing yields, prices, coupons and maturities. Furthermore, depending on the manager’s view on interest rates, they can adjust the average duration of the portfolio accordingly, moving shorter if a rate increase is expected (i.e. buying shorter dated bonds), or longer if a rate cut is expected.
