Inflation-Protected Security (IPS)

What Is an Inflation-Protected Security (IPS)?

An inflation-protected security (IPS) is a type of fixed-income investment that guarantees a real rate of return. This means the annual percentage return realized is adjusted for changes in prices due to inflation or other external effects. Expressing rates of return in real values rather than in non-inflation-adjusted terms, especially during periods of high inflation, offers a clearer picture of an investment's value.

Key Takeaways

  • An inflation-protected security (IPS) is a type of bond that guarantees a real rate of return to its investors.
  • The annual percentage return will fluctuate based on price changes resulting from inflation or other outside factors.
  • Most inflation-protected securities invest in debt securities that have a bond principal that fluctuates depending on inflationary pressures.
  • The U.S. federal government is the main issuer of inflation-protected securities, including Treasury inflation-protected securities (TIPS) and other inflation-protected bonds.
  • Private sector companies also offer similar products, such as corporate inflation-protected securities (CIPS).

Understanding Inflation-Protected Securities (IPS)

Inflation-protected bonds primarily invest in debt securities whose bond principal varies depending on the rate of inflation. The purpose of inflation-indexed investments is to protect an investment’s principal and income stream from the corrosive power of inflation.

The U.S. federal government is currently the leading issuer of these types of securities, primarily in the form of Treasury inflation-protected securities (TIPS) and Series I savings bonds. However, private sector companies also offer these inflation-protected products. One example is corporate inflation-protected securities (CIPS), also referred to as inflation-linked bonds. CIPS are the corporate cousin of TIPS. With the corporate version, the coupon can have a ceiling or not; it can go from a fixed coupon to a floating one, it can be 100% floating and any variation thereof.

All government inflation-indexed securities are benchmarked against the Consumer Price Index (CPI). The CPI measures the prices that consumers pay for frequently purchased items in such industries as transportation, food, and medical care. A sustained increase in the CPI generally indicates that inflation is rising and a dollar’s purchasing power is falling.

Savings vehicles that deliver fixed payouts are particularly vulnerable to the impact of inflation, with higher inflation reducing the value of the payout.

Treasury Inflation-Protected Securities (TIPS)

Treasury inflation-protected securities (TIPS) are U.S. Treasury securities that earn a fixed coupon rate and provide protection against inflation by adjusting the principal by the rate of inflation. During times of inflation, the principal increases; during times of deflation, the principal decreases.

Measured by changes in the Consumer Price Index (CPI) and backed by the government, TIPS can be purchased from a bank, a securities broker, the U.S. Treasury, or a securities dealer. Terms issued are 5, 10, or 30 years, and they are sold in $100 increments.

Interest payments are generated semiannually, with interest applied to the adjusted principal. For example, consider a TIP with a principal value of $2,000 and a coupon rate of 1% during a time when the inflation rate is 5%. The principal is adjusted to the rate of inflation, making it $2,100 ($2,000 x 5%). The interest rate is applied to the adjusted principal balance, resulting in a semiannual payment of $10.5 ($2,100 x .5%) or a total annual payment of $21 ($2,100 x 1%).

TIPS can be sold before maturity or held until their maturity date. When TIPS mature, the greater of the original principal or adjusted principal is paid.

Protecting Fixed Payouts from Inflation

If a savings vehicle is delivering a fixed payout, such as a pension or Social Security, inflation can reduce the value of that payout accordingly. Another example is certificates of deposit (CDs), which investors often use to safely tend to their money and avoid the ups and downs of higher-risk assets, such as stock and bonds. However, for long-term investors, CDs may present a different type of risk that can be just as harmful as market risk—the risk of inflation. If the return on an investment does not at least keep up with the rate of inflation, it will result in the loss of purchasing power over the long term.

To illustrate, if a 5-year CD yielded 2%, but inflation grew by an average of 2.5% during that time frame, an investor’s real rate of return would have been -0.5%. In other words, the investor would have lost money because the investment did not keep up with the rate of inflation.

There are strategies an investor can employ to protect their money from inflation. To keep pace with inflation, investors can invest in Treasury-inflation-protected securities (TIPS), whose principal is adjusted for inflation and deflation. For example, during times of inflation, the principal is increased by the rate of inflation, and its fixed coupon rate is applied to the adjusted principal.

Stocks have historically outpaced inflation and could be a good vehicle for investors with higher risk tolerances. For the risk-averse, mutual funds, precious metals, and exchange-traded funds (ETF) might be a viable option since they are not as sensitive to market changes as with stocks.

For those who want to assume no risk, high-yield fixed accounts may be a favorable option. Although these accounts may not keep pace with inflation, they still offer higher yields than traditional savings accounts.

Can TIPS Lose Money?

The rate of return may be less than the rate of inflation for an investor who holds a TIPS with a negative real yield until maturity. However, TIPS do not lose money. At maturity, the greater of the original principal or the adjusted principal is paid, and interest accrues at a fixed rate.

How Are TIPS Calculated?

TIPS, with coupon rates determined at auction, issue two interest payments annually. The interest payment is determined by multiplying the fixed rate by the adjusted principal. The United States Treasury provides an Index Ratio resource that allows consumers to determine what their inflation-adjusted principal is to calculate their expected interest payment.

Are TIPS Safe Investments?

Because TIPS interest rates do not fluctuate and the principal is adjusted to the rate of inflation, they are relatively safe investments. Also, TIPS are backed by the U.S. government.

How Are Inflation-Linked Bonds Calculated?

Inflation-linked bonds' principal is adjusted for inflation. These bonds earn a fixed coupon rate, which is applied to the adjusted principal.

Article Sources
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  1. U.S. Department of the Treasury. "Treasury Inflation-Protected Securities (TIPS)." Accessed April 2, 2021.

  2. U.S. Department of the Treasury. "Series I Savings Bonds." Accessed April 2, 2021.

  3. U.S. Bureau of Labor Statistics. "Consumer Price Index." Accessed April 2, 2021.

  4. U.S. Department of the Treasury. "Comparison of TIPS and Series I Savings Bonds." Accessed April 2, 2021.

  5. Treasury Direct. "TIPS in Depth." Accessed January 30, 2022.

  6. Treasury Direct. "TIPS/CPI Data."

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