Despite persistent headlines about the strength of the stock market, today’s valuations are flashing a caution light—especially when viewed through the lens of higher interest rates. The S&P 500 is trading well above historical norms, and when adjusted for the current rate environment, valuations may be 25%–30% higher than what fundamentals justify. Add to that a Shiller CAPE (Cyclically Adjusted Price-Earnings ) ratio above 36—levels not seen outside major market bubbles—and the takeaway is clear: investors should temper expectations and prioritize disciplined risk management. Historically, such valuation extremes have been followed by below-average long-term returns, often accompanied by significant short-term volatility. In this article, we explore why managing expectations for future returns is essential in today's environment—and what long-term investors can learn from history.
Valuations Don’t Exist in a Vacuum
The price-to-earnings (P/E) ratio is one of the most widely used tools for evaluating whether the stock market—or individual companies—are fairly valued. A higher P/E suggests that investors are willing to pay more today for a dollar of earnings tomorrow. But this willingness depends heavily on the prevailing interest rates and expected growth.
Why? Because the value of a stock is based on the present value of its future earnings. When interest rates are low, investors can justify paying more (i.e., a higher P/E). But when rates rise, the cost of capital rises too, and the value of future earnings—especially those projected far into the future—falls.
Compounding this challenge is the fiscal backdrop: the U.S. government is carrying historically high levels of debt while running annual deficits in excess of $1 trillion. As of early 2025, the U.S. national debt exceeds $36.5 trillion, and debt-to-GDP stands at approximately 120%—levels not seen since World War II. In fiscal year 2023, net interest costs reached $659 billion, a $184 billion increase from the previous year. According to the Congressional Budget Office (CBO), interest payments are projected to exceed $1 trillion annually by the early 2030s.
These structural imbalances place upward pressure on long-term interest rates. When the supply of government bonds increases to finance deficit spending, yields typically rise unless offset by strong demand. Given the current trajectory of fiscal policy, it is unlikely that we will return to the ultra-low rate environment of the 2010s. Instead, the high debt burden effectively creates a floor under interest rates—acting as a persistent drag on equity valuations and a headwind for future asset returns.
This backdrop reinforces the need for disciplined portfolio construction and careful management of return expectations. If interest rates remain structurally higher due to fiscal conditions, investors may need to adjust their assumptions about future equity performance and plan accordingly.
A Quantitative Comparison
Let’s look at a simplified valuation framework using a version of the Gordon Growth Model:
P/E Ratio ≈ 1 / (r - g)
Where:
- r is the discount rate (interest rate + equity risk premium)
- g is the expected long-term growth rate
Under Lower Interest Rates (e.g., 2020–2021):
- Treasury Yield: ~1.5%
- Equity Risk Premium: ~4.5%
- Implied Discount Rate: ~6.0%
- Expected Growth: ~2.5%
- Fair P/E: ~28.6
Under Today’s Rates (2025):
- Treasury Yield: ~4.5%
- Equity Risk Premium: ~4.0%
- Implied Discount Rate: ~8.5%
- Same Growth: ~2.5%
- Fair P/E: ~16.7
Current S&P 500 forward P/E is ~21—significantly higher than what’s implied by today’s interest rate environment.
What Does the Shiller CAPE Say?
As of May 28, 2025, the Shiller CAPE ratio stands at 36.3, compared to a 20-year average of 26.9. Historically, CAPE levels above 30 have been rare and often preceded extended periods of low returns—such as the dot-com crash and the late 1920s.
The Excess CAPE Yield (ECY), which compares the earnings yield of the market to the yield on 10-year Treasuries, is currently just 1.65%—far below its long-term average of 4.61%. This suggests that investors are being undercompensated for equity risk, increasing long-term downside vulnerability.
Sidebar: Why Use the 20-Year Average?
- Modern Relevance: Reflects current monetary and market structures
- Avoids Skew from Pre-WWII Data
- Balances Short-Term Volatility with Long-Term Insight
- Industry Standard: Commonly used by Vanguard, GMO, Morningstar, etc.
Historical Perspective on High Valuations
Looking back at 1961–1965, when the Shiller CAPE ranged from 21 to 25:
- 10-Year Forward Returns: Averaged 4.5%–6.5%
- But those averages obscure sharp interim declines: Several of these periods experienced market corrections of 20% or more within the decade, often in the first few years.
This highlights a key point: while 10-year average returns may look modest, they often reflect recoveries from significant drawdowns. Investors should anticipate—not be surprised by—short-term volatility when entering at elevated valuations.
Our View
At Crosswalk Investment Advisory, we continue to monitor valuation metrics, interest rates, and economic trends. While equities remain a vital component of long-term wealth building, we believe current conditions call for measured expectations and deliberate diversification.
High-quality holdings, thoughtful allocation, and disciplined risk management will be key in navigating the road ahead.
Disclosures:
This blog post is for informational purposes only and should not be construed as personalized investment advice. Investing involves risk, including the possible loss of principal. Past performance is not indicative of future results. Forward-looking statements are not guarantees. Assumptions and estimates are based on current data as of May 2025 and may change.
Sources:
- U.S. Treasury Monthly Statement (FY 2023)
- Congressional Budget Office, “The Budget and Economic Outlook: 2024 to 2034,” February 2024
- Peter G. Peterson Foundation, “Monthly Interest Tracker”
- Gurufocus.com and YCharts.com for CAPE and ECY data
Content assistance and data organization provided by ChatGPT, a language model developed by OpenAI.