Sanity Dawns
By Peter Brock, July 10, 2026
We are seeing a gradual decline in intrinsic value as corporate bond yields tick higher. In the past, a falling Brock Value is usually followed by a falling S&P 500. In addition to weakening fundamentals, bearish voices like Ed Zitron are opening eyes to the possibility that the AI boom is also a money pit. So far the market is holding up, despite renewed attacks in the Middle East and this dawning sense that we might have gone a little overboard with stock speculation. This tells me that investors are worried more about missing out on higher highs than they are about giving some of their winnings back.
The S&P 500 started to trade in the BV danger zone on March 18, 2022 (when the S&P 500 was 4463). Based on historical relationships, the danger zone begins 30 percent above fair value. This is a risky place to be, where the market is vulnerable to larger than normal bear markets and ten-year expected returns are negative.*
*-1.2% per year over the subsequent decade (median compound annual real total returns, S&P 500, 1960-2025)
| US GDP (Est) | Corp Bond Yield | S&P 500 | Brock Value | Overpriced By |
|---|---|---|---|---|
| $32.1 t | 5.37% | 7575 | 2987 | 154% |
Understanding Brock Value charts
Brock Value is the first clear answer to the question: what is the market worth? BV is a valuation metric with just two inputs: GDP and interest rates. Compared to questionable old-school metrics (and even popular ones like Shiller’s CAPE), BV provides useful measurements which can be used to over or under weight equities in an asset mix.
| Valuation | Returns |
|---|---|
| Above Red Line | -1.2% |
| Fair Value | 6.5% |
| Below Green Line | 10.0% |
| Subsequent 10-year returns, median compound annual real total returns, S&P, 1960-2025 | |
The red and green lines found on most of the Brock Value charts on this site indicate the normal range of the market. The red line indicates 30% overpricing, while the green line represents 20% underpricing. These guidelines serve as boundaries, beyond which valuation is extreme in one direction or the other. When the market (the yellow line) trades above the red line, it is highly overpriced. When this happens, returns over the following ten years tend to be negative. Conversely, when the market trades below the green line, it is underpriced and returns over the next ten years will most likely be much higher than average.

