IBOC vs SPY: Correlation
Measured on weekly returns over the past three years, International Bancshares Corporation (IBOC) and SPDR S&P 500 ETF Trust (SPY) carry a correlation of 0.41, a moderate link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are IBOC and SPY?
On 3 years of weekly data the IBOC/SPY correlation comes out at 0.41, moderate. The link has loosened recently: the 1-year correlation (0.04) runs below the 3-year figure (0.41). The 5-year figure is 0.42, and annualized covariance runs at 160.1 %².
Out of 14 assets tracked against IBOC, SPY lands near the bottom at #10. The last year tells two different stories: SPY led by 21.5 percentage points, -0.9% for IBOC against +20.6% for SPY. One caveat on sizing: IBOC is 1.9 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.
IBOC vs SPY: side by side
| IBOC (International Bancshares Corporation) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | -0.9% | +20.6% |
| 5-year return | +91.3% | +82.4% |
| Volatility (ann.) | 26.9% | 14.5% |
| Beta vs S&P 500 | 0.77 | 1.00 |
| Max drawdown (3Y) | -24.1% | -18.8% |
| Market cap | $4.4B | – |
| P/E (trailing) | 10.7 | – |
| Dividend yield | 2.02% | 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 | IBOC | SPY |
|---|---|---|
| 2022 | +10.9% | -18.2% |
| 2023 | +22.0% | +26.2% |
| 2024 | +19.1% | +24.9% |
| 2025 | +7.4% | +17.7% |
| 2026 | +8.4% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are IBOC and SPY good diversifiers for each other?
A fair diversifier. At 0.41, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
FAQ
What is the correlation between IBOC and SPY?
As of 2026-08-27, the correlation of weekly returns between IBOC and SPY is 0.41 over 3 years, 0.04 over 1 year and 0.42 over 5 years.
Is SPY a good diversifier for IBOC?
A fair diversifier. At 0.41, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
What does a correlation of 0.41 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: IBOC correlations · SPY correlations
