The Shiller P/E ratio, a measure of long-term market valuation, has only crossed 40 three times: 1929, 1999, and today. The first two instances preceded major market crashes (The Great Depression, Dot-com Bust) and were followed by a decade or more of flat or negative real returns for investors.

A key warning sign of a market top is low correlation, where different indices (e.g., NASDAQ, S&P 500, Russell 2000) peak at separate times. This indicates that capital is rotating from exhausted leaders to laggards in a final, desperate search for returns. When this rotation ends, the next likely move is a broad, correlated decline.

Analysis of a proprietary EM FX risk index shows that when an "overbought" signal appears to fail, it's not wrong about the market's condition. Instead, extreme readings predict a delayed correction, typically by about three weeks, as strong positive momentum takes longer to reverse.

A powerful market signal is the "quad count," or the forecasted sequence of economic regimes. A progression from Quad 4 (recession fears) to Quad 3 and then to Quads 2 and 1 creates a powerful contrarian setup. This allows investors to buy assets like small caps when recession probabilities are priced at their highest.

Calling a market top is a technical exercise, as fundamentals lag significantly. A reliable sell signal emerges when the market's leadership narrows to a few "generals." When a critical number of these leaders (e.g., three of the top seven) fall below their 200-day moving average, the rally is likely over.

Calendar year results are arbitrary and can be misleading. A more robust method is to analyze rolling returns, which evaluate performance over fixed periods (e.g., five years) from many different starting points. This method reveals a strategy's true consistency by smoothing out short-term market noise.

The primary indicator of a healthy bull market is when technical breakouts are sustained and lead to higher prices. If breakouts consistently fail and your positions stagnate, it's a red flag that the underlying trend is weakening, even if indices are high.

Anchoring valuation on a company's typical price-to-sales ratio helps identify buying opportunities when margins are temporarily depressed. This avoids the pitfalls of methods like the Magic Formula, which can mistakenly favor companies at their cyclical earnings peaks, leading to underperformance.

Weakness in speculative, low-quality stocks and assets like Bitcoin often marks the beginning of a market correction. The final phase, however, is typically characterized by the decline of high-quality market leaders (the “generals”). This sequential weakness is a historical indicator that the correction is closer to its end than its beginning.