SPY vs TDG: Correlation
Measured on weekly returns over the past three years, SPDR S&P 500 ETF Trust (SPY) and TransDigm Group (TDG) carry a correlation of 0.52, a moderate link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are SPY and TDG?
Over the past 3 years, SPY and TDG moved with a correlation of 0.52, which is moderate. The past 12 months show a weaker link (0.41) than the 3-year average (0.52). Over 5 years the correlation is 0.62, and the annualized covariance of weekly returns is 190.6 %².
Among the 4755 assets we track against SPY, TDG ranks #399 by 3-year correlation. Their recent paths diverged sharply: over the last 12 months SPY outperformed by 29.7 percentage points (+20.6% for SPY against -9.1% for TDG). Across three years, the rolling one-year figure varied moderately, from 0.29 to 0.75. Note the risk asymmetry: TDG runs 1.8 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.
SPY vs TDG: side by side
| SPY (SPDR S&P 500 ETF Trust) | TDG (TransDigm Group) | |
|---|---|---|
| 1-year return | +20.6% | -9.1% |
| 5-year return | +82.4% | +136.5% |
| Volatility (ann.) | 14.5% | 25.5% |
| Beta vs S&P 500 | 1.00 | 0.91 |
| Max drawdown (3Y) | -18.8% | -25.3% |
| Market cap | – | $65.6B |
| P/E (trailing) | – | 36.6 |
| Dividend yield | 1.01% | 0.00% |
| Expense ratio | 0.09% | – |
| Assets under management | $795.3B | – |
| Sector / category | ETF · US Large Cap | Industrials |
On the fund side, SPY sits in the Large Blend category at State Street Investment Management, with $795.3B under management, 504 holdings, a 0.09% expense ratio, a 1.01% trailing dividend yield.
Year-by-year returns
| Year | SPY | TDG |
|---|---|---|
| 2022 | -18.2% | +1.8% |
| 2023 | +26.2% | +66.6% |
| 2024 | +24.9% | +32.3% |
| 2025 | +17.7% | +12.2% |
| 2026 | +13.7% | -10.8% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Fund exposure
A structural note: 0.1% of SPY is TDG itself, so the fund partly moves with the stock by construction.
Are SPY and TDG good diversifiers for each other?
Somewhat, no more. With 0.52 correlation, most large moves hit both names, and the diversification benefit stays modest.
FAQ
What is the correlation between SPY and TDG?
Using weekly returns as of 2026-08-27: 0.52 over 3 years, with 0.41 over the last year and 0.62 over 5 years.
Is TDG a good diversifier for SPY?
Somewhat, no more. With 0.52 correlation, most large moves hit both names, and the diversification benefit stays modest.
What does a correlation of 0.52 mean?
On the −1 to +1 scale, 0.52 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.
Use this data
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Related comparisons
Hubs: SPY correlations · TDG correlations
