IEI focuses on the middle of the US Treasury note market, holding mostly notes maturing between 3 to 7 years. This target pushes IEI's yield up slightly, but also increases the fund's sensitivity to interest rates, as the higher concentration of longer-dated notes in the portfolio will react more to changes in rates. Still, these attributes are perfectly consistent with its tailored exposure. The fund's targeted approach is entirely valid for investors looking for its specific exposure. Unlike some strategies targeting a specific maturity bucket, IEI does not hold STRIPS, meaning all of the notes in the portfolio will be paying out semiannual coupons over the life of the fund. The fund changed its index from the Barclays US Treasury Bond 3-7 Year Term Index to the ICE US Treasury 3-7 Year Bond Index on March 31, 2016. This change effectively maintains the same exposure.