The Treasury Inflation$-$Protected Security $($TIPS$)$ is a bond with a principal value that fluctuates relative to changes in the consumer price index. The interest on the bond is calculated on the adjusted principal. This instrument has an advantage over a regular bond because it: has a real return that is zero. protects the saver against inflation.O protects the saver against supply$-$side shocks.O has a return that matches the ecanomic growth rate.