LII vs MDY: Correlation
How closely do Lennox International (LII) 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 LII and MDY?
On 3 years of weekly data the LII/MDY correlation comes out at 0.53, moderate. Recent behaviour matches the longer record: 0.49 over 1 year against 0.53 over 3. The 5-year figure is 0.60, and annualized covariance runs at 278.5 %².
By 3-year correlation, MDY places #11 of the 37 assets tracked against LII. Their recent paths diverged sharply: over the last 12 months MDY outperformed by 48.6 percentage points (-30.3% for LII against +18.3% for MDY). On a rolling one-year basis the correlation drifted between 0.48 and 0.75, a moderate band. Note the risk asymmetry: LII runs 1.9 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.
LII vs MDY: side by side
| LII (Lennox International) | MDY (SPDR S&P MidCap 400 ETF) | |
|---|---|---|
| 1-year return | -30.3% | +18.3% |
| 5-year return | +23.7% | +47.5% |
| Volatility (ann.) | 32.0% | 16.5% |
| Beta vs S&P 500 | 0.96 | 0.91 |
| Max drawdown (3Y) | -41.7% | -24.0% |
| Market cap | $13.5B | – |
| P/E (trailing) | 17.5 | – |
| Dividend yield | 1.34% | 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 | LII | MDY |
|---|---|---|
| 2022 | -24.9% | -13.3% |
| 2023 | +89.5% | +16.1% |
| 2024 | +37.3% | +13.6% |
| 2025 | -19.5% | +7.2% |
| 2026 | -19.0% | +16.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are LII and MDY good diversifiers for each other?
To a limited degree. At 0.53 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 LII and MDY?
Using weekly returns as of 2026-08-27: 0.53 over 3 years, with 0.49 over the last year and 0.60 over 5 years.
Is MDY a good diversifier for LII?
To a limited degree. At 0.53 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 0.53 mean?
On the −1 to +1 scale, 0.53 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: LII correlations · MDY correlations
