FSP vs MDY: Correlation
Franklin Street Properties Corp. (FSP) and SPDR S&P MidCap 400 ETF (MDY) show a moderate relationship: their 3-year correlation of weekly returns is 0.48.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are FSP and MDY?
Over the past 3 years, FSP and MDY moved with a correlation of 0.48, which is moderate. The relationship has been stable: the 1-year correlation (0.40) sits close to the 3-year figure. Over 5 years the correlation is 0.40, and the annualized covariance of weekly returns is 372.8 %².
Few assets follow FSP as closely as MDY, which ranks #3 of 10 tracked partners. Correlation aside, the last 12 months split them widely, with MDY ahead by 92.9 points (-74.6% versus +18.3%). Note the risk asymmetry: FSP runs 2.9 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.
FSP vs MDY: side by side
| FSP (Franklin Street Properties Corp.) | MDY (SPDR S&P MidCap 400 ETF) | |
|---|---|---|
| 1-year return | -74.6% | +18.3% |
| 5-year return | -89.6% | +47.5% |
| Volatility (ann.) | 47.1% | 16.5% |
| Beta vs S&P 500 | 1.01 | 0.91 |
| Max drawdown (3Y) | -83.8% | -24.0% |
| Market cap | – | – |
| P/E (trailing) | – | – |
| Dividend yield | 4.79% | 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 | FSP | MDY |
|---|---|---|
| 2022 | -52.3% | -13.3% |
| 2023 | -4.1% | +16.1% |
| 2024 | -27.0% | +13.6% |
| 2025 | -46.8% | +7.2% |
| 2026 | -56.2% | +16.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are FSP and MDY good diversifiers for each other?
A fair diversifier. At 0.48, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
FAQ
What is the correlation between FSP and MDY?
Using weekly returns as of 2026-08-27: 0.48 over 3 years, with 0.40 over the last year and 0.40 over 5 years.
Is MDY a good diversifier for FSP?
A fair diversifier. At 0.48, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
What does a correlation of 0.48 mean?
A reading of 0.48 sits on a scale from −1 (opposite moves) through 0 (unrelated) to +1 (identical moves). Correlation captures direction, not magnitude or performance.
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Related comparisons
Hubs: FSP correlations · MDY correlations
