NSC vs SPY: Correlation
Norfolk Southern (NSC) and SPDR S&P 500 ETF Trust (SPY) show a moderate relationship: their 3-year correlation of weekly returns is 0.45.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are NSC and SPY?
On 3 years of weekly data the NSC/SPY correlation comes out at 0.45, moderate. The link has loosened recently: the 1-year correlation (0.02) runs below the 3-year figure (0.45). The 5-year figure is 0.52, and annualized covariance runs at 144.6 %².
By 3-year correlation, SPY places #20 of the 32 assets tracked against NSC. The trailing year gives NSC the advantage: +30.0% versus +20.6%, a 9.4-point spread. This link changes with the market regime, having swung between 0.06 and 0.75 on a rolling one-year basis. Risk is not evenly split, since NSC carries 1.5 times the volatility of the other side.
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.
NSC vs SPY: side by side
| NSC (Norfolk Southern) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +30.0% | +20.6% |
| 5-year return | +49.6% | +82.4% |
| Volatility (ann.) | 22.0% | 14.5% |
| Beta vs S&P 500 | 0.69 | 1.00 |
| Max drawdown (3Y) | -25.1% | -18.8% |
| Market cap | $78.1B | – |
| P/E (trailing) | 30.1 | – |
| Dividend yield | 1.53% | 1.01% |
| Expense ratio | – | 0.09% |
| Assets under management | – | $795.3B |
| Sector / category | Industrials | 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 | NSC | SPY |
|---|---|---|
| 2022 | -15.6% | -18.2% |
| 2023 | -1.6% | +26.2% |
| 2024 | +1.6% | +24.9% |
| 2025 | +25.6% | +17.7% |
| 2026 | +22.0% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Fund exposure
NSC represents 0.12% of SPY's portfolio, so part of any move in SPY is NSC itself, and the correlation between them is partly mechanical.
Are NSC and SPY good diversifiers for each other?
A fair diversifier. At 0.45, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
FAQ
What is the correlation between NSC and SPY?
The NSC/SPY correlation stands at 0.45 on a 3-year window (1 year: 0.02, 5 years: 0.52), computed from weekly returns as of 2026-08-27.
Is SPY a good diversifier for NSC?
A fair diversifier. At 0.45, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
What does a correlation of 0.45 mean?
A reading of 0.45 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: NSC correlations · SPY correlations
