ADTN vs MDY: Correlation
Measured on weekly returns over the past three years, ADTRAN Holdings, Inc. (ADTN) and SPDR S&P MidCap 400 ETF (MDY) 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 ADTN and MDY?
Across a 3-year window, the weekly returns of ADTN and MDY correlate at 0.52, moderate. The past 12 months show a weaker link (0.29) than the 3-year average (0.52). Stretching to 5 years gives 0.46, with an annualized covariance of 485.9 %².
By 3-year correlation, MDY places #5 of the 12 assets tracked against ADTN. Their recent paths diverged sharply: over the last 12 months MDY outperformed by 34.9 percentage points (-16.6% for ADTN against +18.3% for MDY). Risk is not evenly split, since ADTN carries 3.4 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.
ADTN vs MDY: side by side
| ADTN (ADTRAN Holdings, Inc.) | MDY (SPDR S&P MidCap 400 ETF) | |
|---|---|---|
| 1-year return | -16.6% | +18.3% |
| 5-year return | -60.1% | +47.5% |
| Volatility (ann.) | 56.4% | 16.5% |
| Beta vs S&P 500 | 1.55 | 0.91 |
| Max drawdown (3Y) | -61.3% | -24.0% |
| Market cap | $0.6B | – |
| P/E (trailing) | – | – |
| Dividend yield | 0.00% | 1.02% |
| Expense ratio | – | 0.23% |
| Assets under management | – | $26.5B |
| Sector / category | US Listed | 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 | ADTN | MDY |
|---|---|---|
| 2022 | -16.3% | -13.3% |
| 2023 | -59.9% | +16.1% |
| 2024 | +13.5% | +13.6% |
| 2025 | +4.3% | +7.2% |
| 2026 | -10.4% | +16.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are ADTN and MDY good diversifiers for each other?
To a limited degree. At 0.52 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 ADTN and MDY?
As of 2026-08-27, the correlation of weekly returns between ADTN and MDY is 0.52 over 3 years, 0.29 over 1 year and 0.46 over 5 years.
Is MDY a good diversifier for ADTN?
To a limited degree. At 0.52 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 0.52 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.
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Related comparisons
Hubs: ADTN correlations · MDY correlations
