ICUI vs MDY: Correlation
How closely do ICU Medical, Inc. (ICUI) and SPDR S&P MidCap 400 ETF (MDY) 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 ICUI and MDY?
On 3 years of weekly data the ICUI/MDY correlation comes out at 0.50, moderate. Recent behaviour matches the longer record: 0.59 over 1 year against 0.50 over 3. The 5-year figure is 0.49, and annualized covariance runs at 327.4 %².
Among the 16 assets we track against ICUI, MDY ranks #5 by 3-year correlation. Their recent paths diverged sharply: over the last 12 months ICUI outperformed by 20.0 percentage points (+38.3% for ICUI against +18.3% for MDY). One caveat on sizing: ICUI is 2.4 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.
ICUI vs MDY: side by side
| ICUI (ICU Medical, Inc.) | MDY (SPDR S&P MidCap 400 ETF) | |
|---|---|---|
| 1-year return | +38.3% | +18.3% |
| 5-year return | -12.5% | +47.5% |
| Volatility (ann.) | 39.5% | 16.5% |
| Beta vs S&P 500 | 0.84 | 0.91 |
| Max drawdown (3Y) | -45.1% | -24.0% |
| Market cap | $4.4B | – |
| P/E (trailing) | 150.9 | – |
| Dividend yield | 0.00% | 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 | ICUI | MDY |
|---|---|---|
| 2022 | -33.6% | -13.3% |
| 2023 | -36.7% | +16.1% |
| 2024 | +55.6% | +13.6% |
| 2025 | -8.1% | +7.2% |
| 2026 | +22.7% | +16.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are ICUI and MDY 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 ICUI and MDY?
Using weekly returns as of 2026-08-27: 0.50 over 3 years, with 0.59 over the last year and 0.49 over 5 years.
Is MDY a good diversifier for ICUI?
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?
A reading of 0.50 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: ICUI correlations · MDY correlations
