GNRC vs MDY: Correlation
How closely do Generac (GNRC) and SPDR S&P MidCap 400 ETF (MDY) trade together? Their weekly returns over three years give a correlation of 0.53, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are GNRC and MDY?
Across a 3-year window, the weekly returns of GNRC and MDY correlate at 0.53, moderate. The past 12 months show a weaker link (0.40) than the 3-year average (0.53). Stretching to 5 years gives 0.54, with an annualized covariance of 401.5 %².
Within GNRC's tracked universe of 35 assets, MDY comes in at #11 by 3-year correlation. The trailing year gives MDY the advantage: +5.5% versus +18.3%, a 12.8-point spread. Do not treat this figure as fixed: across three years the rolling one-year correlation ranged all the way from 0.17 to 0.77. Risk is not evenly split, since GNRC carries 2.8 times the volatility of the other side.
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.
GNRC vs MDY: side by side
| GNRC (Generac) | MDY (SPDR S&P MidCap 400 ETF) | |
|---|---|---|
| 1-year return | +5.5% | +18.3% |
| 5-year return | -55.4% | +47.5% |
| Volatility (ann.) | 46.1% | 16.5% |
| Beta vs S&P 500 | 1.35 | 0.91 |
| Max drawdown (3Y) | -47.8% | -24.0% |
| Market cap | $11.6B | – |
| P/E (trailing) | 47.4 | – |
| Dividend yield | 0.00% | 1.02% |
| Expense ratio | – | 0.23% |
| Assets under management | – | $26.5B |
| Sector / category | Industrials | 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 | GNRC | MDY |
|---|---|---|
| 2022 | -71.4% | -13.3% |
| 2023 | +28.4% | +16.1% |
| 2024 | +20.0% | +13.6% |
| 2025 | -12.0% | +7.2% |
| 2026 | +44.7% | +16.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are GNRC and MDY good diversifiers for each other?
Only partially. A correlation of 0.53 means GNRC and MDY share most of their swings. Pairing them dampens volatility somewhat, but it will not protect against a common drawdown.
FAQ
What is the correlation between GNRC and MDY?
The GNRC/MDY correlation stands at 0.53 on a 3-year window (1 year: 0.40, 5 years: 0.54), computed from weekly returns as of 2026-08-27.
Is MDY a good diversifier for GNRC?
Only partially. A correlation of 0.53 means GNRC and MDY share most of their swings. Pairing them dampens volatility somewhat, but it will not protect against a common drawdown.
What does a correlation of 0.53 mean?
A reading of 0.53 sits on a scale from −1 (opposite moves) through 0 (unrelated) to +1 (identical moves). Correlation captures direction, not magnitude or performance.
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Related comparisons
Hubs: GNRC correlations · MDY correlations
