RGEN vs SPY: Correlation
Repligen Corporation (RGEN) and SPDR S&P 500 ETF Trust (SPY) show a moderate relationship: their 3-year correlation of weekly returns is 0.40.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are RGEN and SPY?
Over the past 3 years, RGEN and SPY moved with a correlation of 0.40, which is moderate. The relationship has been stable: the 1-year correlation (0.34) sits close to the 3-year figure. Over 5 years the correlation is 0.46, and the annualized covariance of weekly returns is 282.8 %².
Among the 17 assets we track against RGEN, SPY ranks #10 by 3-year correlation. Correlation aside, the last 12 months split them widely, with RGEN ahead by 32.5 points (+53.1% versus +20.6%). Note the risk asymmetry: RGEN 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.
RGEN vs SPY: side by side
| RGEN (Repligen Corporation) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +53.1% | +20.6% |
| 5-year return | -35.6% | +82.4% |
| Volatility (ann.) | 49.5% | 14.5% |
| Beta vs S&P 500 | 1.35 | 1.00 |
| Max drawdown (3Y) | -50.6% | -18.8% |
| Market cap | $10.3B | – |
| P/E (trailing) | 252.8 | – |
| 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 | RGEN | SPY |
|---|---|---|
| 2022 | -36.1% | -18.2% |
| 2023 | +6.2% | +26.2% |
| 2024 | -19.9% | +24.9% |
| 2025 | +13.8% | +17.7% |
| 2026 | +11.1% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are RGEN and SPY good diversifiers for each other?
Reasonably. At 0.40, RGEN and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
FAQ
What is the correlation between RGEN and SPY?
The RGEN/SPY correlation stands at 0.40 on a 3-year window (1 year: 0.34, 5 years: 0.46), computed from weekly returns as of 2026-08-27.
Is SPY a good diversifier for RGEN?
Reasonably. At 0.40, RGEN 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: RGEN correlations · SPY correlations
