Correlation Analysis
Biogen Inc. Common Stock vs Tesla, Inc. Common Stock
BIIB vs TSLA
-0.570
Moderate inverse
When one moves up, the other tends to move down.
Biogen Inc. Common Stock
↗BIIB
Biogen is an established biopharmaceutical company focused on treatments for neurodegenerative and rare diseases. Its declining multiple sclerosis franchise is its largest revenue generator and contributed 40% of total revenue in 2025. Biogen also generates significant revenue from its CD20 collaboration agreements with Roche (19% of total in 2025), which includes oncology drugs Rituxan and Gazyva and multiple sclerosis drug Ocrevus. Biogen's newer franchises include Spinraza (spinal muscular atrophy, with partner Ionis), Leqembi (Alzheimer's disease, collabroation revenue from its partner Eisai), Skyclarys (Friedreich's ataxia, Reata), Zurzuvae (postpartum depression, Sage), and Qalsody (amyotrophic lateral sclerosis, Ionis).
Market cap 25.3B · 7,500 employees
Tesla, Inc. Common Stock
↗TSLA
Tesla is a vertically integrated battery electric vehicle automaker and developer of real world artificial intelligence software, which includes autonomous driving and humanoid robots. The company has multiple vehicles in its fleet, which include luxury and midsize sedans, crossover SUVs, a light truck, and a semi truck. Tesla also plans to begin selling a sports car and offer a robotaxi service. Global deliveries in 2025 were nearly 1.64 million vehicles. The company sells batteries for stationary storage for residential and commercial properties including utilities and solar panels and solar roofs for energy generation. Tesla also owns a fast-charging network and an auto insurance business.
Market cap 1.3T
Time Series
Relative Performance
Who Moves First
TSLA leads BIIB by 4 days
TSLA tends to move before BIIB.
After testing 13 timing shifts, the strongest relationship was -0.573 (they moved in opposite directions).
Do They Crash Together?
Correlation by Market Regime
How these series behave when markets are rising, falling, or diverging. A correlation that holds in drawdowns is very different from one that only works in rallies.
Both Rising
-0.420
12 periods · Return correlation when both series rose
Both Falling
+0.052
13 periods · Return correlation when both series fell
Diverging
-0.731
10 periods · Return correlation when series moved apart
R-Squared
32.5%
Share of variance in one series explained by the other.
Trend Agreement
58.0%
How often both series moved in the same direction period-to-period.
Overlap Quality
1,253
Deep shared window — 1,253 usable pairs.
Significance
p < 0.001
95% CI: [-0.607, -0.532]
Scatter
XY Regression
Pipeline
Data quality details
Pipeline
Data quality details
Pipeline Summary
1,253 paired data points survived the daily window.
Raw input
1,253
1,254
Normalized
1,253
1,254
Prepared
1,253
1,254
Aligned
1,253
1,253
Invalid removed
0
A: 0 / B: 0
Duplicates removed
0
A: 0 / B: 0
Alignment drops
1
A: 0 / B: 1
Series A
Biogen Inc. Common Stock
BIIB
Market cap 25.3B · 7,500 employees
Stock · 1,253 raw → 1,253 prepared
Series B
Tesla, Inc. Common Stock
TSLA
Market cap 1.3T
Stock · 1,254 raw → 1,254 prepared
Sign agreement
100.0%
How often both values share the same sign.
Zero crossings
19
Estimated crossover points between normalized spreads.
Slope
-0.7952
Linear regression slope.
Intercept
451.4795
Linear regression intercept.
Related Extremes
Highest and Lowest Correlated
Saved 7 hours ago · ID: stock-biib-vs-stock-tsla-daily