The Pearson Correlation Coefficient (r) ranges from −1.0 to +1.0 and measures the degree to which two ETFs move together on a daily basis.
Correlation Formula & Interpretation
r(X, Y) = Cov(R_X, R_Y) / (σ_X × σ_Y)
- r close to +1.0 (e.g., 0.95+): The two ETFs move almost identically (such as E1VFVN30 and FUESSV30, which both track VN30).
- r between 0.60 and 0.85: Moderate-to-high equity co-movement with meaningful factor differentiation (e.g., combining VN30 with FUEVFVND or FUEDCMID).
Inspect the live 252-day pairwise correlation matrix in our Portfolio Risk & Correlation Analyzer.