BELFB vs SPY: Correlation
Bel Fuse Inc. (BELFB) and SPDR S&P 500 ETF Trust (SPY) show a moderate relationship: their 3-year correlation of weekly returns is 0.38.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are BELFB and SPY?
On 3 years of weekly data the BELFB/SPY correlation comes out at 0.38, moderate. The relationship has been stable: the 1-year correlation (0.35) sits close to the 3-year figure. The 5-year figure is 0.43, and annualized covariance runs at 271.1 %².
Among the 14 assets we track against BELFB, SPY ranks #8 by 3-year correlation. The last year tells two different stories: BELFB led by 63.1 percentage points, +83.7% for BELFB against +20.6% for SPY. Note the risk asymmetry: BELFB runs 3.4 times the annualized volatility of the other leg, so equal-weighting the two is not an equal-risk position.
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.
BELFB vs SPY: side by side
| BELFB (Bel Fuse Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +83.7% | +20.6% |
| 5-year return | +1827.0% | +82.4% |
| Volatility (ann.) | 49.1% | 14.5% |
| Beta vs S&P 500 | 1.30 | 1.00 |
| Max drawdown (3Y) | -33.4% | -18.8% |
| Market cap | $3.7B | – |
| P/E (trailing) | 65.2 | – |
| Dividend yield | 0.09% | 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 | BELFB | SPY |
|---|---|---|
| 2022 | +158.7% | -18.2% |
| 2023 | +104.2% | +26.2% |
| 2024 | +24.0% | +24.9% |
| 2025 | +106.3% | +17.7% |
| 2026 | +52.0% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are BELFB and SPY good diversifiers for each other?
Reasonably. At 0.38, BELFB and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
FAQ
What is the correlation between BELFB and SPY?
The BELFB/SPY correlation stands at 0.38 on a 3-year window (1 year: 0.35, 5 years: 0.43), computed from weekly returns as of 2026-08-27.
Is SPY a good diversifier for BELFB?
Reasonably. At 0.38, BELFB and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
What does a correlation of 0.38 mean?
Correlation ranges from −1 to +1. Values near +1 mean two assets move together, near 0 that they move independently, and negative values that they tend to move in opposite directions. It measures co-movement, not performance.
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Hubs: BELFB correlations · SPY correlations
