HDSN vs SPY: Correlation
Hudson Technologies, Inc. (HDSN) and SPDR S&P 500 ETF Trust (SPY) show a weak relationship: their 3-year correlation of weekly returns is 0.26.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are HDSN and SPY?
On 3 years of weekly data the HDSN/SPY correlation comes out at 0.26, weak. Recent behaviour matches the longer record: 0.31 over 1 year against 0.26 over 3. The 5-year figure is 0.21, and annualized covariance runs at 155.1 %².
Within HDSN's tracked universe of 12 assets, SPY comes in at #7 by 3-year correlation. The last year tells two different stories: SPY led by 67.1 percentage points, -46.5% for HDSN against +20.6% for SPY. Risk is not evenly split, since HDSN carries 2.9 times the volatility of the other side.
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.
HDSN vs SPY: side by side
| HDSN (Hudson Technologies, Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | -46.5% | +20.6% |
| 5-year return | +68.6% | +82.4% |
| Volatility (ann.) | 41.6% | 14.5% |
| Beta vs S&P 500 | 0.74 | 1.00 |
| Max drawdown (3Y) | -67.6% | -18.8% |
| Market cap | $0.2B | – |
| P/E (trailing) | 24.9 | – |
| 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 | HDSN | SPY |
|---|---|---|
| 2022 | +127.9% | -18.2% |
| 2023 | +33.3% | +26.2% |
| 2024 | -58.6% | +24.9% |
| 2025 | +22.8% | +17.7% |
| 2026 | -20.0% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are HDSN and SPY good diversifiers for each other?
Reasonably. At 0.26, HDSN and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
FAQ
What is the correlation between HDSN and SPY?
As of 2026-08-27, the correlation of weekly returns between HDSN and SPY is 0.26 over 3 years, 0.31 over 1 year and 0.21 over 5 years.
Is SPY a good diversifier for HDSN?
Reasonably. At 0.26, HDSN and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
What does a correlation of 0.26 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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Related comparisons
Hubs: HDSN correlations · SPY correlations
