MDY vs XLF: Correlation & Overlap
How closely do SPDR S&P MidCap 400 ETF (MDY) and Financial Select Sector SPDR Fund (XLF) trade together? Their weekly returns over three years give a correlation of 0.79, which is strong. The two funds also share 0% of their portfolios by weight.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are MDY and XLF?
Across a 3-year window, the weekly returns of MDY and XLF correlate at 0.79, strong. The past 12 months show a weaker link (0.57) than the 3-year average (0.79). Stretching to 5 years gives 0.83, with an annualized covariance of 209.7 %².
By 3-year correlation, XLF places #25 of the 359 assets tracked against MDY. On 12-month performance MDY holds a 9.0-point edge, +18.3% against +9.3%. On a rolling one-year basis the correlation drifted between 0.58 and 0.92, a moderate band.
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 XLF: side by side
| MDY (SPDR S&P MidCap 400 ETF) | XLF (Financial Select Sector SPDR Fund) | |
|---|---|---|
| 1-year return | +18.3% | +9.3% |
| 5-year return | +47.5% | +64.2% |
| Volatility (ann.) | 16.5% | 16.2% |
| Beta vs S&P 500 | 0.91 | 0.84 |
| Max drawdown (3Y) | -24.0% | -15.5% |
| Dividend yield | 1.02% | 1.42% |
| Expense ratio | 0.23% | 0.08% |
| Assets under management | $26.5B | $57.9B |
| Sector / category | ETF · US Small & Mid Cap | Sector ETF |
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. XLF is a Financial fund from State Street Investment Management: $57.9B under management, 77 holdings, a 0.08% expense ratio, a 1.42% trailing dividend yield.
Portfolio overlap between MDY and XLF
The two portfolios are largely distinct. Weighing the shared positions, 0% of the two funds is identical, spread across 0 common holdings. That shared book is a large part of why the returns line up.
Largest positions held only by MDY: TWLO (0.95%), P (0.94%), ILMN (0.93%), FTI (0.83%), ATI (0.80%). Only by XLF: JPM (11.61%), BRK.B (11.25%), V (7.74%), MA (5.87%), BAC (4.94%).
Overlap = sum of the smaller of the two weights across common holdings, from issuer disclosures as of 2026-08-26.
Year-by-year returns
| Year | MDY | XLF |
|---|---|---|
| 2022 | -13.3% | -10.6% |
| 2023 | +16.1% | +12.0% |
| 2024 | +13.6% | +30.6% |
| 2025 | +7.2% | +14.9% |
| 2026 | +16.4% | +6.6% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are MDY and XLF good diversifiers for each other?
Somewhat, no more. With 0.79 correlation, most large moves hit both names, and the diversification benefit stays modest.
FAQ
What is the correlation between MDY and XLF?
Using weekly returns as of 2026-08-27: 0.79 over 3 years, with 0.57 over the last year and 0.83 over 5 years.
Is XLF a good diversifier for MDY?
Somewhat, no more. With 0.79 correlation, most large moves hit both names, and the diversification benefit stays modest.
How much do MDY and XLF overlap?
Per the issuers' own portfolio disclosures (2026-08-26), the overlap is 0% by weight over 0 common positions.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/mdy-vs-xlf.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/mdy-vs-xlf/)
Free with attribution; caching and terms are described in the API documentation.
Related comparisons
Hubs: MDY correlations · XLF correlations
