Performance Comparison: Stratum Index vs. SPY and Core Algorithm (2008–2025) This chart highlights the long-term performance of the Stratum Index alongside SPY and the standalone Core Algorithm. Starting from the aftermath of the 2008 crisis through the rate-driven volatility of 2022–2025, the Stratum Index shows its strength in adapting across economic cycles. While SPY reflects broad market exposure and the Core Algorithm tracks a single signal, the full Index blends six models for greater resilience, smoother returns, and reduced drawdowns.