GERN vs SPY: Correlation
How closely do Geron Corporation (GERN) and SPDR S&P 500 ETF Trust (SPY) trade together? Their weekly returns over three years give a correlation of 0.30, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are GERN and SPY?
Over the past 3 years, GERN and SPY moved with a correlation of 0.30, which is moderate. Little has changed lately, as the 1-year reading of 0.32 lands near the 3-year figure. Over 5 years the correlation is 0.27, and the annualized covariance of weekly returns is 280.6 %².
Among the 11 assets we track against GERN, SPY sits near the bottom by co-movement, at rank #7. On 12-month performance SPY holds a 12.1-point edge, +8.5% against +20.6%. Note the risk asymmetry: GERN runs 4.4 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.
GERN vs SPY: side by side
| GERN (Geron Corporation) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +8.5% | +20.6% |
| 5-year return | +6.2% | +82.4% |
| Volatility (ann.) | 64.0% | 14.5% |
| Beta vs S&P 500 | 1.34 | 1.00 |
| Max drawdown (3Y) | -79.0% | -18.8% |
| Market cap | $1.0B | – |
| 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 | GERN | SPY |
|---|---|---|
| 2022 | +98.4% | -18.2% |
| 2023 | -12.8% | +26.2% |
| 2024 | +67.8% | +24.9% |
| 2025 | -62.7% | +17.7% |
| 2026 | +15.9% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are GERN and SPY good diversifiers for each other?
A fair diversifier. At 0.30, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
FAQ
What is the correlation between GERN and SPY?
Using weekly returns as of 2026-08-27: 0.30 over 3 years, with 0.32 over the last year and 0.27 over 5 years.
Is SPY a good diversifier for GERN?
A fair diversifier. At 0.30, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
What does a correlation of 0.30 mean?
On the −1 to +1 scale, 0.30 describes how much the two returns move together: +1 is lockstep, 0 is independence, negative values mean opposite directions. It says nothing about which performed better.
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Related comparisons
Hubs: GERN correlations · SPY correlations
