MDY vs WOR: Correlation
How closely do SPDR S&P MidCap 400 ETF (MDY) and Worthington Enterprises, Inc. (WOR) trade together? Their weekly returns over three years give a correlation of 0.50, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are MDY and WOR?
Across a 3-year window, the weekly returns of MDY and WOR correlate at 0.50, moderate. Recent behaviour matches the longer record: 0.54 over 1 year against 0.50 over 3. Stretching to 5 years gives 0.59, with an annualized covariance of 285.8 %².
By 3-year correlation, WOR places #297 of the 359 assets tracked against MDY. Their recent paths diverged sharply: over the last 12 months MDY outperformed by 31.4 percentage points (+18.3% for MDY against -13.1% for WOR). One caveat on sizing: WOR is 2.1 times as volatile as the other leg, so an equal-dollar split is far from equal-risk.
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.
MDY vs WOR: side by side
| MDY (SPDR S&P MidCap 400 ETF) | WOR (Worthington Enterprises, Inc.) | |
|---|---|---|
| 1-year return | +18.3% | -13.1% |
| 5-year return | +47.5% | +73.3% |
| Volatility (ann.) | 16.5% | 34.7% |
| Beta vs S&P 500 | 0.91 | 0.83 |
| Max drawdown (3Y) | -24.0% | -42.4% |
| Market cap | – | $2.8B |
| P/E (trailing) | – | 18.5 |
| Dividend yield | 1.02% | 1.31% |
| Expense ratio | 0.23% | – |
| Assets under management | $26.5B | – |
| Sector / category | ETF · US Small & Mid Cap | US Listed |
On the fund side, MDY sits in the Mid-Cap Blend category at State Street Investment Management, with $26.5B under management, 400 holdings, a 0.23% expense ratio, a 1.02% trailing dividend yield.
Year-by-year returns
| Year | MDY | WOR |
|---|---|---|
| 2022 | -13.3% | -6.9% |
| 2023 | +16.1% | +91.6% |
| 2024 | +13.6% | -29.3% |
| 2025 | +7.2% | +30.3% |
| 2026 | +16.4% | +12.9% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are MDY and WOR good diversifiers for each other?
Somewhat, no more. With 0.50 correlation, most large moves hit both names, and the diversification benefit stays modest.
FAQ
What is the correlation between MDY and WOR?
As of 2026-08-27, the correlation of weekly returns between MDY and WOR is 0.50 over 3 years, 0.54 over 1 year and 0.59 over 5 years.
Is WOR a good diversifier for MDY?
Somewhat, no more. With 0.50 correlation, most large moves hit both names, and the diversification benefit stays modest.
What does a correlation of 0.50 mean?
On the −1 to +1 scale, 0.50 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
$ curl https://www.pairbook.io/api/v1/pairs/mdy-vs-wor.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/mdy-vs-wor/)
No key needed, free to use. Full endpoint list in the API documentation.
Related comparisons
Hubs: MDY correlations · WOR correlations
