The Wall Street Journal reports that the equity risk premium (ERP) – the extra return investors have historically demanded for owning stocks over bonds – has effectively disappeared. This phenomenon, where the earnings yield on equities is now on par with or even below the yield on investment-grade bonds, challenges a long-standing tenet of financial markets.

Despite this shift in the ERP, there's little evidence of waning demand for equities, particularly among individual investors. These retail participants, buoyed by two years of significant market gains, remain broadly bullish on stocks, continuing to allocate capital to equity markets.

The disappearance of the ERP suggests that the potential for outsized returns from stocks relative to bonds has diminished. This could imply either that bonds are now relatively more attractive, or that stock valuations are stretched, compressing future equity returns. The divergence between this historical market signal and current investor behavior sets up a potential inflection point for asset allocation decisions.

Investors are left to weigh whether the recent bullish sentiment can sustain equity performance in an environment where the 'extra reward' has vanished, or if a re-evaluation of risk-adjusted returns will eventually lead to a rotation out of equities and into fixed income. The resilience of retail demand will be a key factor to watch.