SPY vs SRTA: Correlation
How closely do SPDR S&P 500 ETF Trust (SPY) and Strata Critical Medical, Inc. (SRTA) trade together? Their weekly returns over three years give a correlation of 0.42, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are SPY and SRTA?
Over the past 3 years, SPY and SRTA moved with a correlation of 0.42, which is moderate. Little has changed lately, as the 1-year reading of 0.44 lands near the 3-year figure. Over 5 years the correlation is 0.41, and the annualized covariance of weekly returns is 421.7 %².
Among the 4755 assets we track against SPY, SRTA ranks #987 by 3-year correlation. Over the last 12 months SRTA came out ahead by 14.1 percentage points (+20.6% against +34.7%). One caveat on sizing: SRTA is 4.8 times as volatile as the other leg, so an equal-dollar split is far from equal-risk.
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.
SPY vs SRTA: side by side
| SPY (SPDR S&P 500 ETF Trust) | SRTA (Strata Critical Medical, Inc.) | |
|---|---|---|
| 1-year return | +20.6% | +34.7% |
| 5-year return | +82.4% | -28.6% |
| Volatility (ann.) | 14.5% | 69.8% |
| Beta vs S&P 500 | 1.00 | 2.02 |
| Max drawdown (3Y) | -18.8% | -48.9% |
| Market cap | – | $0.5B |
| P/E (trailing) | – | – |
| Dividend yield | 1.01% | 0.00% |
| Expense ratio | 0.09% | – |
| Assets under management | $795.3B | – |
| Sector / category | ETF · US Large Cap | US Listed |
SPY, State Street Investment Management's Large Blend fund, carries $795.3B under management, 504 holdings, a 0.09% expense ratio, a 1.01% trailing dividend yield.
Year-by-year returns
| Year | SPY | SRTA |
|---|---|---|
| 2022 | -18.2% | -59.5% |
| 2023 | +26.2% | -1.4% |
| 2024 | +24.9% | +20.4% |
| 2025 | +17.7% | +13.2% |
| 2026 | +13.7% | +28.3% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are SPY and SRTA good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.42 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between SPY and SRTA?
Using weekly returns as of 2026-08-27: 0.42 over 3 years, with 0.44 over the last year and 0.41 over 5 years.
Is SRTA a good diversifier for SPY?
Yes, to a useful degree: a correlation of 0.42 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.42 mean?
On the −1 to +1 scale, 0.42 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.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/spy-vs-srta.json
Drop this badge in a README or notebook; it updates with the data:
[](https://www.pairbook.io/pair/spy-vs-srta/)
No key needed, free to use. Full endpoint list in the API documentation.
Related comparisons
Hubs: SPY correlations · SRTA correlations
