SPY vs STIM: Correlation
How closely do SPDR S&P 500 ETF Trust (SPY) and Neuronetics, Inc. (STIM) trade together? Their weekly returns over three years give a correlation of 0.24, which is weak.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are SPY and STIM?
On 3 years of weekly data the SPY/STIM correlation comes out at 0.24, weak. Recent behaviour matches the longer record: 0.32 over 1 year against 0.24 over 3. The 5-year figure is 0.27, and annualized covariance runs at 383.3 %².
Among the 4755 assets we track against SPY, STIM ranks #2882 by 3-year correlation. The last year tells two different stories: SPY led by 32.5 percentage points, +20.6% for SPY against -11.9% for STIM. One caveat on sizing: STIM is 7.5 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 STIM: side by side
| SPY (SPDR S&P 500 ETF Trust) | STIM (Neuronetics, Inc.) | |
|---|---|---|
| 1-year return | +20.6% | -11.9% |
| 5-year return | +82.4% | -54.7% |
| Volatility (ann.) | 14.5% | 109.2% |
| Beta vs S&P 500 | 1.00 | 1.83 |
| Max drawdown (3Y) | -18.8% | -87.3% |
| Market cap | – | $0.2B |
| 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 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 | SPY | STIM |
|---|---|---|
| 2022 | -18.2% | +54.0% |
| 2023 | +26.2% | -57.8% |
| 2024 | +24.9% | -44.5% |
| 2025 | +17.7% | -14.3% |
| 2026 | +13.7% | +114.5% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are SPY and STIM good diversifiers for each other?
A fair diversifier. At 0.24, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
FAQ
What is the correlation between SPY and STIM?
As of 2026-08-27, the correlation of weekly returns between SPY and STIM is 0.24 over 3 years, 0.32 over 1 year and 0.27 over 5 years.
Is STIM a good diversifier for SPY?
A fair diversifier. At 0.24, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
What does a correlation of 0.24 mean?
A reading of 0.24 sits on a scale from −1 (opposite moves) through 0 (unrelated) to +1 (identical moves). Correlation captures direction, not magnitude or performance.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/spy-vs-stim.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/spy-vs-stim/)
Free with attribution; caching and terms are described in the API documentation.
Related comparisons
Hubs: SPY correlations · STIM correlations
