CBT vs SPY: Correlation
How closely do Cabot Corporation (CBT) and SPDR S&P 500 ETF Trust (SPY) trade together? Their weekly returns over three years give a correlation of 0.43, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are CBT and SPY?
Over the past 3 years, CBT and SPY moved with a correlation of 0.43, which is moderate. The link has loosened recently: the 1-year correlation (0.21) runs below the 3-year figure (0.43). Over 5 years the correlation is 0.50, and the annualized covariance of weekly returns is 176.0 %².
By 3-year correlation, SPY places #10 of the 15 assets tracked against CBT. On 12-month performance SPY holds a 14.9-point edge, +5.7% against +20.6%. Note the risk asymmetry: CBT runs 2.0 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.
CBT vs SPY: side by side
| CBT (Cabot Corporation) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +5.7% | +20.6% |
| 5-year return | +73.1% | +82.4% |
| Volatility (ann.) | 28.5% | 14.5% |
| Beta vs S&P 500 | 0.84 | 1.00 |
| Max drawdown (3Y) | -48.8% | -18.8% |
| Market cap | $4.4B | – |
| P/E (trailing) | 23.7 | – |
| Dividend yield | 2.16% | 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 | CBT | SPY |
|---|---|---|
| 2022 | +21.4% | -18.2% |
| 2023 | +27.6% | +26.2% |
| 2024 | +11.3% | +24.9% |
| 2025 | -25.7% | +17.7% |
| 2026 | +29.1% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are CBT and SPY good diversifiers for each other?
Reasonably. At 0.43, CBT and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
FAQ
What is the correlation between CBT and SPY?
As of 2026-08-27, the correlation of weekly returns between CBT and SPY is 0.43 over 3 years, 0.21 over 1 year and 0.50 over 5 years.
Is SPY a good diversifier for CBT?
Reasonably. At 0.43, CBT and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
What does a correlation of 0.43 mean?
A reading of 0.43 sits on a scale from −1 (opposite moves) through 0 (unrelated) to +1 (identical moves). Correlation captures direction, not magnitude or performance.
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Related comparisons
Hubs: CBT correlations · SPY correlations
