CLFD vs SPY: Correlation
How closely do Clearfield, Inc. (CLFD) and SPDR S&P 500 ETF Trust (SPY) trade together? Their weekly returns over three years give a correlation of 0.40, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are CLFD and SPY?
On 3 years of weekly data the CLFD/SPY correlation comes out at 0.40, moderate. The relationship has been stable: the 1-year correlation (0.36) sits close to the 3-year figure. The 5-year figure is 0.42, and annualized covariance runs at 280.9 %².
Out of 12 assets tracked against CLFD, SPY lands near the bottom at #8. The last year tells two different stories: SPY led by 29.1 percentage points, -8.5% for CLFD against +20.6% for SPY. Note the risk asymmetry: CLFD 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.
CLFD vs SPY: side by side
| CLFD (Clearfield, Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | -8.5% | +20.6% |
| 5-year return | -35.2% | +82.4% |
| Volatility (ann.) | 49.0% | 14.5% |
| Beta vs S&P 500 | 1.34 | 1.00 |
| Max drawdown (3Y) | -48.0% | -18.8% |
| Market cap | $0.4B | – |
| P/E (trailing) | 103.3 | – |
| Dividend yield | 0.00% | 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 | CLFD | SPY |
|---|---|---|
| 2022 | +11.5% | -18.2% |
| 2023 | -69.1% | +26.2% |
| 2024 | +6.6% | +24.9% |
| 2025 | -6.0% | +17.7% |
| 2026 | +2.8% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are CLFD and SPY good diversifiers for each other?
Reasonably. At 0.40, CLFD and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
FAQ
What is the correlation between CLFD and SPY?
As of 2026-08-27, the correlation of weekly returns between CLFD and SPY is 0.40 over 3 years, 0.36 over 1 year and 0.42 over 5 years.
Is SPY a good diversifier for CLFD?
Reasonably. At 0.40, CLFD and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
What does a correlation of 0.40 mean?
A reading of 0.40 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: CLFD correlations · SPY correlations
