MCK vs SPY: Correlation
Measured on weekly returns over the past three years, McKesson Corporation (MCK) and SPDR S&P 500 ETF Trust (SPY) carry a correlation of 0.09, a near-zero link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are MCK and SPY?
Across a 3-year window, the weekly returns of MCK and SPY correlate at 0.09, near zero, meaning they move largely independently. Lately the two have drifted apart, with the 1-year correlation at -0.08 versus 0.09 over 3 years. Stretching to 5 years gives 0.22, with an annualized covariance of 34.1 %².
Among the 35 assets we track against MCK, SPY ranks #20 by 3-year correlation. The trailing year gives MCK the advantage: +30.8% versus +20.6%, a 10.2-point spread. Do not treat this figure as fixed: across three years the rolling one-year correlation ranged all the way from -0.10 to 0.42. One caveat on sizing: MCK is 1.7 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.
MCK vs SPY: side by side
| MCK (McKesson Corporation) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +30.8% | +20.6% |
| 5-year return | +354.8% | +82.4% |
| Volatility (ann.) | 25.1% | 14.5% |
| Beta vs S&P 500 | 0.16 | 1.00 |
| Max drawdown (3Y) | -27.2% | -18.8% |
| Market cap | $103.8B | – |
| P/E (trailing) | 24.0 | – |
| Dividend yield | 0.37% | 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 | MCK | SPY |
|---|---|---|
| 2022 | +51.8% | -18.2% |
| 2023 | +24.1% | +26.2% |
| 2024 | +23.7% | +24.9% |
| 2025 | +44.5% | +17.7% |
| 2026 | +8.8% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Fund exposure
A structural note: 0.16% of SPY is MCK itself, so the fund partly moves with the stock by construction.
Are MCK and SPY good diversifiers for each other?
Yes: at 0.09, the two have gone their own ways historically, which is what genuine diversification looks like.
FAQ
What is the correlation between MCK and SPY?
The MCK/SPY correlation stands at 0.09 on a 3-year window (1 year: -0.08, 5 years: 0.22), computed from weekly returns as of 2026-08-27.
Is SPY a good diversifier for MCK?
Yes: at 0.09, the two have gone their own ways historically, which is what genuine diversification looks like.
What does a correlation of 0.09 mean?
On the −1 to +1 scale, 0.09 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.
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Related comparisons
Hubs: MCK correlations · SPY correlations
