JETS vs MDY: Correlation
US Global Jets ETF (JETS) and SPDR S&P MidCap 400 ETF (MDY) show a strong relationship: their 3-year correlation of weekly returns is 0.71.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are JETS and MDY?
Across a 3-year window, the weekly returns of JETS and MDY correlate at 0.71, strong. Recent behaviour matches the longer record: 0.78 over 1 year against 0.71 over 3. Stretching to 5 years gives 0.73, with an annualized covariance of 339.1 %².
By 3-year correlation, MDY places #9 of the 54 assets tracked against JETS. On 12-month performance MDY holds a 5.1-point edge, +13.2% against +18.3%. On a rolling one-year basis the correlation drifted between 0.44 and 0.86, a moderate band. Note the risk asymmetry: JETS 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.
JETS vs MDY: side by side
| JETS (US Global Jets ETF) | MDY (SPDR S&P MidCap 400 ETF) | |
|---|---|---|
| 1-year return | +13.2% | +18.3% |
| 5-year return | +30.9% | +47.5% |
| Volatility (ann.) | 29.2% | 16.5% |
| Beta vs S&P 500 | 1.16 | 0.91 |
| Max drawdown (3Y) | -35.2% | -24.0% |
| Dividend yield | – | 1.02% |
| Expense ratio | – | 0.23% |
| Assets under management | – | $26.5B |
| Sector / category | ETF · Thematic | ETF · US Small & Mid Cap |
MDY, State Street Investment Management's Mid-Cap Blend fund, carries $26.5B under management, 400 holdings, a 0.23% expense ratio, a 1.02% trailing dividend yield.
Year-by-year returns
| Year | JETS | MDY |
|---|---|---|
| 2022 | -19.0% | -13.3% |
| 2023 | +11.4% | +16.1% |
| 2024 | +33.2% | +13.6% |
| 2025 | +11.6% | +7.2% |
| 2026 | +4.6% | +16.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are JETS and MDY good diversifiers for each other?
To a limited degree. At 0.71 the two still catch most of the same waves, so the pair smooths returns a little without insulating either from a shared selloff.
FAQ
What is the correlation between JETS and MDY?
The JETS/MDY correlation stands at 0.71 on a 3-year window (1 year: 0.78, 5 years: 0.73), computed from weekly returns as of 2026-08-27.
Is MDY a good diversifier for JETS?
To a limited degree. At 0.71 the two still catch most of the same waves, so the pair smooths returns a little without insulating either from a shared selloff.
What does a correlation of 0.71 mean?
On the −1 to +1 scale, 0.71 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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Hubs: JETS correlations · MDY correlations
