The Role of Bonds in a New Era of Low Yields

August 2020 was a month for the record books, just a few months removed from quite possibly the deepest but shortest recession in modern times. With U.S. 10-year Treasury yields setting record lows, and U.S equities (S&P 500) hitting record highs, some investors are questioning whether traditional core fixed income can still serve as effectively as a ballast in portfolios.

The interest rate sensitivity of core bonds has historically served as a diversifier to equities, providing price appreciation potential and resiliency in the face of stock market declines. Core bonds generally have been used to help dampen overall portfolio volatility while pursuing attractive returns that can outpace inflation.

Let’s look at how the traditional appeal of core bonds stacks up today.

Re-examining the value proposition of traditional fixed income

Dampening volatility: In isolation, core bonds display higher volatility than cash. However, in a portfolio that includes equity and other riskier holdings, core bonds have historically offered a reduction in volatility similar to that achieved by holding cash, but with higher returns (see chart). This volatility-dampening benefit is a function of the generally negative correlation that core bonds can display to equities. Even with interest rates somewhat range-bound at lower levels, we believe this correlation benefit should persist – that is, rates could still go lower in a negative growth scenario when equities and risk assets underperform.

Using data going back 20 years from 31 August 2020, the chart compares the return versus volatility tradeoff of a portfolio comprised only of US stocks, versus a portfolio comprised of 60% US stocks and 40% US bonds, and a portfolio of 60% US stocks and 40% US cash. Substituting either bonds or cash, the volatility of the whole portfolio declines by a similar amount, going from roughly 15% for an all stock portfolio to about 9% for a 60/40 portfolio using either bonds or cash for the 40% component. The difference, though, is that the 60/40 portfolio with bonds as the 40% component has a higher return of 6.1% versus the portfolio that uses cash for the 40% component, which returns 4.7% percent. Bonds are represented by the Bloomberg Barclays U.S. Aggregate Index, Cash represented by the FTSE US 3-Month Treasury Bill Index and stocks represented by the S&P 500 Index.Image Pop Up

Diversifying risk assets in periods of market stress: Core bonds also have had the ability to provide positive return potential when riskier assets face drawdowns. This is because interest rates tend to fall (benefiting rate-sensitive assets) when credit or equity performance is challenged (e.g., by the end of Q1, the Bloomberg Barclays U.S. Aggregate Index (“U.S. Aggregate Index”) was up 3.15% when the S&P 500 was down 19.60%). With interest rates at today’s low levels, the room to decline is potentially more limited than before – but rates can still fall even in what will likely remain a fairly range-bound rate environment. Moreover, to the extent a more negative growth scenario were to take hold, we would expect rates to decline substantially and thus deliver price appreciation potential (a severe negative shock could push yields to zero, and with 10-year Treasuries yielding about 0.7% lately, a decline to 0% yield would imply price appreciation of over 4%i).