CI vs SPY: Correlation
Measured on weekly returns over the past three years, Cigna (CI) and SPDR S&P 500 ETF Trust (SPY) carry a correlation of 0.12, a weak link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are CI and SPY?
Across a 3-year window, the weekly returns of CI and SPY correlate at 0.12, weak. Recent behaviour matches the longer record: 0.02 over 1 year against 0.12 over 3. Stretching to 5 years gives 0.22, with an annualized covariance of 45.4 %².
Among the 30 assets we track against CI, SPY ranks #19 by 3-year correlation. Correlation aside, the last 12 months split them widely, with SPY ahead by 26.0 points (-5.4% versus +20.6%). On a rolling one-year basis the correlation drifted between -0.01 and 0.25, a moderate band. Note the risk asymmetry: CI runs 1.8 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.
CI vs SPY: side by side
| CI (Cigna) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | -5.4% | +20.6% |
| 5-year return | +46.7% | +82.4% |
| Volatility (ann.) | 26.7% | 14.5% |
| Beta vs S&P 500 | 0.22 | 1.00 |
| Max drawdown (3Y) | -32.1% | -18.8% |
| Market cap | $73.4B | – |
| P/E (trailing) | 11.6 | – |
| Dividend yield | 2.19% | 1.01% |
| Expense ratio | – | 0.09% |
| Assets under management | – | $795.3B |
| Sector / category | Health Care | 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 | CI | SPY |
|---|---|---|
| 2022 | +46.7% | -18.2% |
| 2023 | -8.0% | +26.2% |
| 2024 | -6.3% | +24.9% |
| 2025 | +1.7% | +17.7% |
| 2026 | +2.0% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Fund exposure
Keep in mind that SPY holds CI at a 0.11% weight, which makes a slice of this correlation mechanical rather than coincidental.
Are CI and SPY good diversifiers for each other?
Yes: at 0.12, the two have gone their own ways historically, which is what genuine diversification looks like.
FAQ
What is the correlation between CI and SPY?
Using weekly returns as of 2026-08-27: 0.12 over 3 years, with 0.02 over the last year and 0.22 over 5 years.
Is SPY a good diversifier for CI?
Yes: at 0.12, the two have gone their own ways historically, which is what genuine diversification looks like.
What does a correlation of 0.12 mean?
A reading of 0.12 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: CI correlations · SPY correlations
