FULC vs XBI: Correlation
Measured on weekly returns over the past three years, Fulcrum Therapeutics, Inc. (FULC) and SPDR S&P Biotech ETF (XBI) carry a correlation of 0.44, a moderate link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are FULC and XBI?
Across a 3-year window, the weekly returns of FULC and XBI correlate at 0.44, moderate. Recent behaviour matches the longer record: 0.41 over 1 year against 0.44 over 3. Stretching to 5 years gives 0.48, with an annualized covariance of 1120.7 %².
XBI is one of the assets that tracks FULC most closely: it ranks #1 out of the 11 assets we track against FULC. Correlation aside, the last 12 months split them widely, with XBI ahead by 129.1 points (-41.9% versus +87.2%). Risk is not evenly split, since FULC carries 3.4 times the volatility of the other side.
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.
FULC vs XBI: side by side
| FULC (Fulcrum Therapeutics, Inc.) | XBI (SPDR S&P Biotech ETF) | |
|---|---|---|
| 1-year return | -41.9% | +87.2% |
| 5-year return | -86.0% | +28.6% |
| Volatility (ann.) | 92.9% | 27.7% |
| Beta vs S&P 500 | 1.49 | 1.09 |
| Max drawdown (3Y) | -79.1% | -33.0% |
| Market cap | $0.3B | – |
| P/E (trailing) | – | – |
| Dividend yield | 0.00% | – |
| Sector / category | US Listed | ETF · Thematic |
Year-by-year returns
| Year | FULC | XBI |
|---|---|---|
| 2022 | -58.8% | -25.9% |
| 2023 | -7.3% | +7.6% |
| 2024 | -30.4% | +1.0% |
| 2025 | +140.6% | +35.9% |
| 2026 | -66.0% | +38.1% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are FULC and XBI good diversifiers for each other?
Reasonably. At 0.44, FULC and XBI keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
FAQ
What is the correlation between FULC and XBI?
The FULC/XBI correlation stands at 0.44 on a 3-year window (1 year: 0.41, 5 years: 0.48), computed from weekly returns as of 2026-08-27.
Is XBI a good diversifier for FULC?
Reasonably. At 0.44, FULC and XBI keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
What does a correlation of 0.44 mean?
On the −1 to +1 scale, 0.44 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
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Related comparisons
Hubs: FULC correlations · XBI correlations
