FIBK vs SPY: Correlation
Measured on weekly returns over the past three years, First Interstate BancSystem, Inc. (FIBK) and SPDR S&P 500 ETF Trust (SPY) carry a correlation of 0.47, a moderate link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are FIBK and SPY?
Over the past 3 years, FIBK and SPY moved with a correlation of 0.47, which is moderate. Lately the two have drifted apart, with the 1-year correlation at 0.26 versus 0.47 over 3 years. Over 5 years the correlation is 0.41, and the annualized covariance of weekly returns is 205.5 %².
By 3-year correlation, SPY places #14 of the 20 assets tracked against FIBK. Neither side won the trailing year by much: +21.9% against +20.6%. Note the risk asymmetry: FIBK runs 2.1 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.
FIBK vs SPY: side by side
| FIBK (First Interstate BancSystem, Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +21.9% | +20.6% |
| 5-year return | +13.8% | +82.4% |
| Volatility (ann.) | 30.3% | 14.5% |
| Beta vs S&P 500 | 0.98 | 1.00 |
| Max drawdown (3Y) | -31.8% | -18.8% |
| Market cap | $3.6B | – |
| P/E (trailing) | 11.5 | – |
| Dividend yield | 5.05% | 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 | FIBK | SPY |
|---|---|---|
| 2022 | -0.8% | -18.2% |
| 2023 | -14.8% | +26.2% |
| 2024 | +12.9% | +24.9% |
| 2025 | +13.5% | +17.7% |
| 2026 | +11.8% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are FIBK and SPY good diversifiers for each other?
A fair diversifier. At 0.47, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
FAQ
What is the correlation between FIBK and SPY?
Using weekly returns as of 2026-08-27: 0.47 over 3 years, with 0.26 over the last year and 0.41 over 5 years.
Is SPY a good diversifier for FIBK?
A fair diversifier. At 0.47, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
What does a correlation of 0.47 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: FIBK correlations · SPY correlations
