In the United States, a
savings bond with an inflation-indexed interest rate. This bond pays a fixed
coupon plus an amount adjusted every six months according to the
Consumer Price Index. These bonds are sold at
face value and
pay par upon
maturity, which is 30 years after purchase. Series I bonds not held for at least five years are subject to a
redemption penalty. Federal taxes on interest are deferred until redemption or maturity. Savings bonds are non-transferrable and must either be held or redeemed.