BLK vs SPY: Correlation
Measured on weekly returns over the past three years, BlackRock (BLK) and SPDR S&P 500 ETF Trust (SPY) carry a correlation of 0.69, a strong link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are BLK and SPY?
Over the past 3 years, BLK and SPY moved with a correlation of 0.69, which is strong. The past 12 months show a weaker link (0.56) than the 3-year average (0.69). Over 5 years the correlation is 0.77, and the annualized covariance of weekly returns is 248.2 %².
By 3-year correlation, SPY places #10 of the 42 assets tracked against BLK. Their recent paths diverged sharply: over the last 12 months SPY outperformed by 15.3 percentage points (+5.3% for BLK against +20.6% for SPY). On a rolling one-year basis the correlation drifted between 0.53 and 0.84, a moderate band. One caveat on sizing: BLK is 1.7 times as volatile as the other leg, so an equal-dollar split is far from equal-risk.
How is this computed?
Pearson correlation on weekly returns: ρ(A,B) = cov(rA, rB) / (σA · σB), over windows of 52, 156 and 260 weeks. Covariance is annualized (×52) and expressed in %². Full definitions on the methodology page.
BLK vs SPY: side by side
| BLK (BlackRock) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +5.3% | +20.6% |
| 5-year return | +38.9% | +82.4% |
| Volatility (ann.) | 24.7% | 14.5% |
| Beta vs S&P 500 | 1.19 | 1.00 |
| Max drawdown (3Y) | -23.7% | -18.8% |
| Market cap | $189.7B | – |
| P/E (trailing) | 28.1 | – |
| Dividend yield | 1.86% | 1.01% |
| Expense ratio | – | 0.09% |
| Assets under management | – | $795.3B |
| Sector / category | Financials | ETF · US Large Cap |
SPY is a Large Blend fund from State Street Investment Management: $795.3B under management, 504 holdings, a 0.09% expense ratio, a 1.01% trailing dividend yield.
Year-by-year returns
| Year | BLK | SPY |
|---|---|---|
| 2022 | -20.4% | -18.2% |
| 2023 | +17.9% | +26.2% |
| 2024 | +29.3% | +24.9% |
| 2025 | +6.6% | +17.7% |
| 2026 | +10.3% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Fund exposure
BLK represents 0.26% of SPY's portfolio, so part of any move in SPY is BLK itself, and the correlation between them is partly mechanical.
Are BLK and SPY good diversifiers for each other?
Somewhat, no more. With 0.69 correlation, most large moves hit both names, and the diversification benefit stays modest.
FAQ
What is the correlation between BLK and SPY?
Using weekly returns as of 2026-08-27: 0.69 over 3 years, with 0.56 over the last year and 0.77 over 5 years.
Is SPY a good diversifier for BLK?
Somewhat, no more. With 0.69 correlation, most large moves hit both names, and the diversification benefit stays modest.
What does a correlation of 0.69 mean?
On the −1 to +1 scale, 0.69 describes how much the two returns move together: +1 is lockstep, 0 is independence, negative values mean opposite directions. It says nothing about which performed better.
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Related comparisons
Hubs: BLK correlations · SPY correlations
