PACB vs XBI: Correlation
Pacific Biosciences of California, Inc. (PACB) and SPDR S&P Biotech ETF (XBI) show a moderate relationship: their 3-year correlation of weekly returns is 0.47.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are PACB and XBI?
Over the past 3 years, PACB and XBI moved with a correlation of 0.47, which is moderate. The relationship has been stable: the 1-year correlation (0.46) sits close to the 3-year figure. Over 5 years the correlation is 0.57, and the annualized covariance of weekly returns is 1219.3 %².
By 3-year correlation, XBI places #5 of the 11 assets tracked against PACB. Their recent paths diverged sharply: over the last 12 months XBI outperformed by 70.7 percentage points (+16.5% for PACB against +87.2% for XBI). Note the risk asymmetry: PACB runs 3.4 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.
PACB vs XBI: side by side
| PACB (Pacific Biosciences of California, Inc.) | XBI (SPDR S&P Biotech ETF) | |
|---|---|---|
| 1-year return | +16.5% | +87.2% |
| 5-year return | -94.9% | +28.6% |
| Volatility (ann.) | 93.3% | 27.7% |
| Beta vs S&P 500 | 1.21 | 1.09 |
| Max drawdown (3Y) | -92.2% | -33.0% |
| Market cap | $0.5B | – |
| P/E (trailing) | – | – |
| Dividend yield | 0.00% | – |
| Sector / category | US Listed | ETF · Thematic |
Year-by-year returns
| Year | PACB | XBI |
|---|---|---|
| 2022 | -60.0% | -25.9% |
| 2023 | +19.9% | +7.6% |
| 2024 | -81.3% | +1.0% |
| 2025 | +2.2% | +35.9% |
| 2026 | -17.1% | +38.1% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are PACB and XBI good diversifiers for each other?
Reasonably. At 0.47, PACB and XBI keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
FAQ
What is the correlation between PACB and XBI?
The PACB/XBI correlation stands at 0.47 on a 3-year window (1 year: 0.46, 5 years: 0.57), computed from weekly returns as of 2026-08-27.
Is XBI a good diversifier for PACB?
Reasonably. At 0.47, PACB and XBI keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
What does a correlation of 0.47 mean?
On the −1 to +1 scale, 0.47 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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Embed this badge (it refreshes with the data), with attribution:
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Related comparisons
Hubs: PACB correlations · XBI correlations
