CTOS vs SPY: Correlation
How closely do Custom Truck One Source, Inc. (CTOS) and SPDR S&P 500 ETF Trust (SPY) trade together? Their weekly returns over three years give a correlation of 0.38, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are CTOS and SPY?
Across a 3-year window, the weekly returns of CTOS and SPY correlate at 0.38, moderate. Lately the two have drifted apart, with the 1-year correlation at 0.27 versus 0.38 over 3 years. Stretching to 5 years gives 0.43, with an annualized covariance of 296.1 %².
By 3-year correlation, SPY places #8 of the 13 assets tracked against CTOS. The last year tells two different stories: CTOS led by 40.7 percentage points, +61.3% for CTOS against +20.6% for SPY. One caveat on sizing: CTOS is 3.8 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.
CTOS vs SPY: side by side
| CTOS (Custom Truck One Source, Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +61.3% | +20.6% |
| 5-year return | +8.1% | +82.4% |
| Volatility (ann.) | 54.4% | 14.5% |
| Beta vs S&P 500 | 1.42 | 1.00 |
| Max drawdown (3Y) | -55.6% | -18.8% |
| Market cap | $2.2B | – |
| P/E (trailing) | 107.3 | – |
| 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 | CTOS | SPY |
|---|---|---|
| 2022 | -21.0% | -18.2% |
| 2023 | -2.2% | +26.2% |
| 2024 | -22.2% | +24.9% |
| 2025 | +19.8% | +17.7% |
| 2026 | +67.7% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are CTOS and SPY good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.38 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between CTOS and SPY?
As of 2026-08-27, the correlation of weekly returns between CTOS and SPY is 0.38 over 3 years, 0.27 over 1 year and 0.43 over 5 years.
Is SPY a good diversifier for CTOS?
Yes, to a useful degree: a correlation of 0.38 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.38 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: CTOS correlations · SPY correlations
