Joe Wiesenthal and Tracy Alloway host Jonathan Heathcote, an economist at the Minneapolis Federal Reserve, to discuss his research on stock market valuations and macroeconomic factors. Heathcote co-authored A Macroeconomic Perspective on Stock Market Valuation Ratios, published in January 2024, which challenges conventional wisdom about overvalued markets.

The conversation explores why traditional valuation metrics like the Shiller CAPE ratio have failed to predict mean reversion, while examining the current shift in big tech from cash generation to massive AI-related capital expenditure. The discussion covers declining labor share, free cash flow analysis, and the potential implications of artificial intelligence for both corporate profits and income inequality.

Why Traditional Valuation Metrics May Be Misleading

Heathcote's research in A Macroeconomic Perspective on Stock Market Valuation Ratios shows that while price-earnings ratios have drifted persistently higher since 1952, price-to-free-cash-flow ratios have remained within historical ranges.

"If you look at that ratio the value of all the firms in the US relative to the total cash flow they're generating, it bounces around a bunch over time, but it doesn't have like a long, long term drift" - Jonathan

Free cash flow represents money left after paying all bills including capital expenditure, making it a cleaner measure of returns available to shareholders than earnings.

The ratio was the same in 1980 (a market low) and Q2 2022, both at historical averages, though it has risen above average in the past three years.

The Declining Labor Share Driving Higher Profits

Corporate sector wages and salaries have fallen by eight percentage points of GDP since 1980, representing a massive shift from labor to capital.

"Earnings have grown, but cash flow has grown even faster. And cash flows grown even faster because firms have been able to generate these extra earnings without doing a lot of extra investment" - Jonathan

The measurement uses robust national accounts data for the corporate sector, where distinguishing labor from capital payments is straightforward, unlike small businesses.

Stock-based compensation complicates the picture but is partially captured in standard wage measures when options are exercised.

Big Tech's Shift From Cash Generation to AI Investment

The largest tech companies have historically been "machines generating cash without a lot of capital expenditure" but are now spending heavily on AI infrastructure.

Fifty firms account for most US stock market value growth, with cash flow and valuations rising together for these companies over time.

"Some of these companies whose cash flow temporarily is negative right now. They used to make big free cash flow, and so that's the question investors are thinking about" - Jonathan

While AI investment has boomed, other investment categories like residential have remained weak, keeping aggregate investment levels relatively normal.

Historical Parallels and Future Implications for AI

The early 1980s saw low stock prices due to uncertainty about the IT revolution's winners and losers, similar to current AI uncertainty.

The dot-com boom represented "irrational exuberance" with weak cash flow and sky-high valuations, though some technologies eventually paid off years later.

AI could reduce labor share further while requiring substantial capital expenditure, creating competing forces for valuations going forward.

"I think this idea that you know AI is kind of there for free that you can just adopt it and get these bigger profits without any investments. I think that's not going to be quite right" - Jonathan

Policy Implications and Financial Stability Concerns

The Federal Reserve monitors equity markets as tailwinds or headwinds for the economy, with higher stock prices supporting consumer spending and business investment.

High current valuations create larger downside risks for household wealth if stock prices fall substantially, raising financial stability concerns.

"A ten percent fall in prices when prices are really high is going to be a larger fall in household wealth than a ten percent fall when prices are low" - Jonathan

The research suggests investors may rationally switch between valuation metrics, using free cash flow when convenient and earnings ratios when cash flow looks weak.