MASS vs SPY: Correlation
Measured on weekly returns over the past three years, 908 Devices Inc. (MASS) and SPDR S&P 500 ETF Trust (SPY) carry a correlation of 0.27, a weak link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are MASS and SPY?
On 3 years of weekly data the MASS/SPY correlation comes out at 0.27, weak. The past 12 months show a tighter link (0.38) than the 3-year average (0.27). The 5-year figure is 0.35, and annualized covariance runs at 322.8 %².
Out of 10 assets tracked against MASS, SPY lands near the bottom at #6. Correlation aside, the last 12 months split them widely, with MASS ahead by 55.6 points (+76.2% versus +20.6%). Note the risk asymmetry: MASS runs 5.7 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.
MASS vs SPY: side by side
| MASS (908 Devices Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +76.2% | +20.6% |
| 5-year return | -69.9% | +82.4% |
| Volatility (ann.) | 82.7% | 14.5% |
| Beta vs S&P 500 | 1.55 | 1.00 |
| Max drawdown (3Y) | -84.9% | -18.8% |
| Market cap | $0.5B | – |
| 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 | MASS | SPY |
|---|---|---|
| 2022 | -70.5% | -18.2% |
| 2023 | +47.2% | +26.2% |
| 2024 | -80.4% | +24.9% |
| 2025 | +138.6% | +17.7% |
| 2026 | +111.4% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are MASS and SPY good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.27 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between MASS and SPY?
As of 2026-08-27, the correlation of weekly returns between MASS and SPY is 0.27 over 3 years, 0.38 over 1 year and 0.35 over 5 years.
Is SPY a good diversifier for MASS?
Yes, to a useful degree: a correlation of 0.27 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.27 mean?
On the −1 to +1 scale, 0.27 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: MASS correlations · SPY correlations
