JILL vs MDY: Correlation
Measured on weekly returns over the past three years, J. Jill, Inc. (JILL) and SPDR S&P MidCap 400 ETF (MDY) carry a correlation of 0.49, a moderate link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are JILL and MDY?
Across a 3-year window, the weekly returns of JILL and MDY correlate at 0.49, moderate. Little has changed lately, as the 1-year reading of 0.42 lands near the 3-year figure. Stretching to 5 years gives 0.45, with an annualized covariance of 386.8 %².
MDY is one of the assets that tracks JILL most closely: it ranks #3 out of the 14 assets we track against JILL. Twelve-month performance is nearly a tie, at +18.8% for JILL and +18.3% for MDY. Note the risk asymmetry: JILL 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.
JILL vs MDY: side by side
| JILL (J. Jill, Inc.) | MDY (SPDR S&P MidCap 400 ETF) | |
|---|---|---|
| 1-year return | +18.8% | +18.3% |
| 5-year return | -1.2% | +47.5% |
| Volatility (ann.) | 47.4% | 16.5% |
| Beta vs S&P 500 | 1.17 | 0.91 |
| Max drawdown (3Y) | -71.5% | -24.0% |
| Market cap | $0.3B | – |
| P/E (trailing) | 14.5 | – |
| Dividend yield | 1.66% | 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 | JILL | MDY |
|---|---|---|
| 2022 | +29.3% | -13.3% |
| 2023 | +4.0% | +16.1% |
| 2024 | +7.9% | +13.6% |
| 2025 | -49.3% | +7.2% |
| 2026 | +46.5% | +16.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are JILL and MDY good diversifiers for each other?
A fair diversifier. At 0.49, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
FAQ
What is the correlation between JILL and MDY?
Using weekly returns as of 2026-08-27: 0.49 over 3 years, with 0.42 over the last year and 0.45 over 5 years.
Is MDY a good diversifier for JILL?
A fair diversifier. At 0.49, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
What does a correlation of 0.49 mean?
Correlation ranges from −1 to +1. Values near +1 mean two assets move together, near 0 that they move independently, and negative values that they tend to move in opposite directions. It measures co-movement, not performance.
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Related comparisons
Hubs: JILL correlations · MDY correlations
