IRDM vs SPY: Correlation
Iridium Communications Inc (IRDM) and SPDR S&P 500 ETF Trust (SPY) show a weak relationship: their 3-year correlation of weekly returns is 0.25.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are IRDM and SPY?
Over the past 3 years, IRDM and SPY moved with a correlation of 0.25, which is weak. Little has changed lately, as the 1-year reading of 0.30 lands near the 3-year figure. Over 5 years the correlation is 0.26, and the annualized covariance of weekly returns is 178.0 %².
Within IRDM's tracked universe of 12 assets, SPY comes in at #7 by 3-year correlation. Their recent paths diverged sharply: over the last 12 months IRDM outperformed by 74.8 percentage points (+95.4% for IRDM against +20.6% for SPY). One caveat on sizing: IRDM is 3.4 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.
IRDM vs SPY: side by side
| IRDM (Iridium Communications Inc) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +95.4% | +20.6% |
| 5-year return | +8.5% | +82.4% |
| Volatility (ann.) | 49.3% | 14.5% |
| Beta vs S&P 500 | 0.85 | 1.00 |
| Max drawdown (3Y) | -67.5% | -18.8% |
| Market cap | $5.0B | – |
| P/E (trailing) | 54.1 | – |
| Dividend yield | 1.27% | 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 | IRDM | SPY |
|---|---|---|
| 2022 | +24.5% | -18.2% |
| 2023 | -19.1% | +26.2% |
| 2024 | -28.1% | +24.9% |
| 2025 | -38.5% | +17.7% |
| 2026 | +176.6% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are IRDM and SPY good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.25 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between IRDM and SPY?
As of 2026-08-27, the correlation of weekly returns between IRDM and SPY is 0.25 over 3 years, 0.30 over 1 year and 0.26 over 5 years.
Is SPY a good diversifier for IRDM?
Yes, to a useful degree: a correlation of 0.25 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.25 mean?
On the −1 to +1 scale, 0.25 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: IRDM correlations · SPY correlations
