ALDX vs SPY: Correlation
Aldeyra Therapeutics, Inc. (ALDX) and SPDR S&P 500 ETF Trust (SPY) show a moderate relationship: their 3-year correlation of weekly returns is 0.42.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are ALDX and SPY?
On 3 years of weekly data the ALDX/SPY correlation comes out at 0.42, moderate. Recent behaviour matches the longer record: 0.39 over 1 year against 0.42 over 3. The 5-year figure is 0.35, and annualized covariance runs at 653.0 %².
By 3-year correlation, SPY places #8 of the 13 assets tracked against ALDX. The last year tells two different stories: SPY led by 94.3 percentage points, -73.7% for ALDX against +20.6% for SPY. Note the risk asymmetry: ALDX runs 7.4 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.
ALDX vs SPY: side by side
| ALDX (Aldeyra Therapeutics, Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | -73.7% | +20.6% |
| 5-year return | -83.1% | +82.4% |
| Volatility (ann.) | 107.4% | 14.5% |
| Beta vs S&P 500 | 3.13 | 1.00 |
| Max drawdown (3Y) | -83.8% | -18.8% |
| Market cap | $0.1B | – |
| P/E (trailing) | – | – |
| 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 | ALDX | SPY |
|---|---|---|
| 2022 | +74.0% | -18.2% |
| 2023 | -49.6% | +26.2% |
| 2024 | +42.2% | +24.9% |
| 2025 | +3.8% | +17.7% |
| 2026 | -70.3% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are ALDX and SPY good diversifiers for each other?
A fair diversifier. At 0.42, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
FAQ
What is the correlation between ALDX and SPY?
Using weekly returns as of 2026-08-27: 0.42 over 3 years, with 0.39 over the last year and 0.35 over 5 years.
Is SPY a good diversifier for ALDX?
A fair diversifier. At 0.42, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
What does a correlation of 0.42 mean?
A reading of 0.42 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: ALDX correlations · SPY correlations
