MDY vs URI: Correlation
SPDR S&P MidCap 400 ETF (MDY) and United Rentals (URI) show a strong relationship: their 3-year correlation of weekly returns is 0.69.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are MDY and URI?
Across a 3-year window, the weekly returns of MDY and URI correlate at 0.69, strong. The past 12 months show a weaker link (0.45) than the 3-year average (0.69). Stretching to 5 years gives 0.74, with an annualized covariance of 449.9 %².
Among the 359 assets we track against MDY, URI ranks #73 by 3-year correlation. The trailing year gives MDY the advantage: +18.3% versus +10.2%, a 8.1-point spread. The rolling one-year correlation moved between 0.44 and 0.86 over the past three years, a moderate range. Note the risk asymmetry: URI runs 2.4 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.
MDY vs URI: side by side
| MDY (SPDR S&P MidCap 400 ETF) | URI (United Rentals) | |
|---|---|---|
| 1-year return | +18.3% | +10.2% |
| 5-year return | +47.5% | +204.1% |
| Volatility (ann.) | 16.5% | 39.5% |
| Beta vs S&P 500 | 0.91 | 1.42 |
| Max drawdown (3Y) | -24.0% | -37.0% |
| Market cap | – | $64.6B |
| P/E (trailing) | – | 25.4 |
| Dividend yield | 1.02% | 0.71% |
| Expense ratio | 0.23% | – |
| Assets under management | $26.5B | – |
| Sector / category | ETF · US Small & Mid Cap | Industrials |
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 | URI |
|---|---|---|
| 2022 | -13.3% | +7.0% |
| 2023 | +16.1% | +63.6% |
| 2024 | +13.6% | +24.0% |
| 2025 | +7.2% | +15.9% |
| 2026 | +16.4% | +29.0% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are MDY and URI good diversifiers for each other?
Only partially. A correlation of 0.69 means MDY and URI 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 MDY and URI?
The MDY/URI correlation stands at 0.69 on a 3-year window (1 year: 0.45, 5 years: 0.74), computed from weekly returns as of 2026-08-27.
Is URI a good diversifier for MDY?
Only partially. A correlation of 0.69 means MDY and URI share most of their swings. Pairing them dampens volatility somewhat, but it will not protect against a common drawdown.
What does a correlation of 0.69 mean?
On the −1 to +1 scale, 0.69 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-uri.json
Markdown for the live badge, attribution link included:
[](https://www.pairbook.io/pair/mdy-vs-uri/)
The core API is free. Terms and every endpoint in the API documentation.
Related comparisons
Hubs: MDY correlations · URI correlations
