BLFS vs SPY: Correlation
Measured on weekly returns over the past three years, BioLife Solutions, Inc. (BLFS) and SPDR S&P 500 ETF Trust (SPY) carry a correlation of 0.48, a moderate link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are BLFS and SPY?
Over the past 3 years, BLFS and SPY moved with a correlation of 0.48, which is moderate. Lately the two have drifted apart, with the 1-year correlation at 0.22 versus 0.48 over 3 years. Over 5 years the correlation is 0.51, and the annualized covariance of weekly returns is 345.8 %².
By 3-year correlation, SPY places #10 of the 15 assets tracked against BLFS. Correlation aside, the last 12 months split them widely, with BLFS ahead by 25.7 points (+46.3% versus +20.6%). Note the risk asymmetry: BLFS runs 3.5 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.
BLFS vs SPY: side by side
| BLFS (BioLife Solutions, Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +46.3% | +20.6% |
| 5-year return | -36.2% | +82.4% |
| Volatility (ann.) | 50.1% | 14.5% |
| Beta vs S&P 500 | 1.66 | 1.00 |
| Max drawdown (3Y) | -37.0% | -18.8% |
| Market cap | $1.8B | – |
| P/E (trailing) | 37.2 | – |
| 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 | BLFS | SPY |
|---|---|---|
| 2022 | -51.2% | -18.2% |
| 2023 | -10.7% | +26.2% |
| 2024 | +59.8% | +24.9% |
| 2025 | -6.9% | +17.7% |
| 2026 | +53.8% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are BLFS and SPY good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.48 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between BLFS and SPY?
As of 2026-08-27, the correlation of weekly returns between BLFS and SPY is 0.48 over 3 years, 0.22 over 1 year and 0.51 over 5 years.
Is SPY a good diversifier for BLFS?
Yes, to a useful degree: a correlation of 0.48 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.48 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: BLFS correlations · SPY correlations
