MYI vs SPY: Correlation
How closely do Blackrock MuniYield Quality Fund III, Inc (MYI) and SPDR S&P 500 ETF Trust (SPY) trade together? Their weekly returns over three years give a correlation of 0.37, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are MYI and SPY?
Across a 3-year window, the weekly returns of MYI and SPY correlate at 0.37, moderate. The link has tightened recently: the 1-year correlation (0.50) runs above the 3-year figure (0.37). Stretching to 5 years gives 0.45, with an annualized covariance of 62.2 %².
Among the 15 assets we track against MYI, SPY sits near the bottom by co-movement, at rank #11. On 12-month performance SPY holds a 11.9-point edge, +8.7% against +20.6%.
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.
MYI vs SPY: side by side
| MYI (Blackrock MuniYield Quality Fund III, Inc) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +8.7% | +20.6% |
| 5-year return | -5.8% | +82.4% |
| Volatility (ann.) | 11.8% | 14.5% |
| Beta vs S&P 500 | 0.30 | 1.00 |
| Max drawdown (3Y) | -11.8% | -18.8% |
| Market cap | – | – |
| P/E (trailing) | 28.3 | – |
| Dividend yield | 6.20% | 1.01% |
| Expense ratio | – | 0.09% |
| Assets under management | – | $795.3B |
| Sector / category | US Listed | 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 | MYI | SPY |
|---|---|---|
| 2022 | -20.5% | -18.2% |
| 2023 | +8.8% | +26.2% |
| 2024 | +0.6% | +24.9% |
| 2025 | +4.8% | +17.7% |
| 2026 | +3.2% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are MYI and SPY good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.37 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between MYI and SPY?
Using weekly returns as of 2026-08-27: 0.37 over 3 years, with 0.50 over the last year and 0.45 over 5 years.
Is SPY a good diversifier for MYI?
Yes, to a useful degree: a correlation of 0.37 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.37 mean?
A reading of 0.37 sits on a scale from −1 (opposite moves) through 0 (unrelated) to +1 (identical moves). Correlation captures direction, not magnitude or performance.
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Related comparisons
Hubs: MYI correlations · SPY correlations
