BIIB vs PFE: Correlation
How closely do Biogen (BIIB) and Pfizer (PFE) trade together? Their weekly returns over three years give a correlation of 0.49, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are BIIB and PFE?
Over the past 3 years, BIIB and PFE moved with a correlation of 0.49, which is moderate. Recent behaviour matches the longer record: 0.50 over 1 year against 0.49 over 3. Over 5 years the correlation is 0.36, and the annualized covariance of weekly returns is 350.2 %².
Among the 32 assets we track against BIIB, PFE ranks #6 by 3-year correlation. Correlation aside, the last 12 months split them widely, with BIIB ahead by 42.8 points (+62.4% versus +19.6%). The relationship is regime-dependent: the rolling one-year correlation swung between 0.15 and 0.76 over the past three years, so this pair behaves very differently depending on the market environment.
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.
BIIB vs PFE: side by side
| BIIB (Biogen) | PFE (Pfizer) | |
|---|---|---|
| 1-year return | +62.4% | +19.6% |
| 5-year return | -35.7% | -21.9% |
| Volatility (ann.) | 30.1% | 23.8% |
| Beta vs S&P 500 | 0.53 | 0.40 |
| Max drawdown (3Y) | -57.7% | -34.8% |
| Market cap | $32.7B | $159.7B |
| P/E (trailing) | 39.2 | 37.4 |
| Dividend yield | 0.00% | 6.08% |
| Sector / category | Health Care | Health Care |
Year-by-year returns
| Year | BIIB | PFE |
|---|---|---|
| 2022 | +15.4% | -10.4% |
| 2023 | -6.6% | -41.3% |
| 2024 | -40.9% | -2.2% |
| 2025 | +15.1% | +0.6% |
| 2026 | +25.9% | +18.3% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are BIIB and PFE 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 BIIB and PFE?
The BIIB/PFE correlation stands at 0.49 on a 3-year window (1 year: 0.50, 5 years: 0.36), computed from weekly returns as of 2026-08-27.
Is PFE a good diversifier for BIIB?
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: BIIB correlations · PFE correlations
