Correlation Analysis
BERKSHIRE HATHAWAY Class B vs Cummins Inc.
BRK.B vs CMI
+0.782
Strong positive
When one moves up, the other tends to follow.
BERKSHIRE HATHAWAY Class B
↗BRK.B
Berkshire Hathaway is a holding company with a wide array of subsidiaries engaged in diverse activities. The firm's core business segment is insurance, run primarily through Geico, Berkshire Hathaway Reinsurance Group, and Berkshire Hathaway Primary Group. Berkshire has used the excess cash thrown off from its operations to acquire Burlington Northern Santa Fe (railroad), Berkshire Hathaway Energy (utilities and energy distributors), and the companies that make up its manufacturing, service, and retailing operations (which include Precision Castparts, Lubrizol, Clayton Homes, Marmon, and IMC/ISCAR). The conglomerate is unique in that it is run on a completely decentralized basis. Berkshire is expected to generate close to $375 billion in revenue in 2025.
Market cap 1T
Cummins Inc.
↗CMI
Cummins is a leading manufacturer of diesel and other engines used in heavy- and medium-duty commercial trucks, off-highway equipment, and locomotives, in addition to prime power and standby generators. The company also sells powertrain components, which include filtration products, transmissions, turbochargers, aftertreatment systems, and fuel systems. Sales are approximately 60% US and Canada and 40% rest of the world. Much of Cummins' foreign sales (China, India, and so forth) are through joint ventures. The company operates 650 distributors and over 19,000 dealer locations across 190 countries. Cummins' business model is unique as it competes with many of its heavy-duty truck manufacturer customers, which also make their own engines.
Market cap 76.3B · 67,400 employees
Time Series
Relative Performance
Who Moves First
BRK.B leads CMI by 6 days
BRK.B tends to move before CMI.
After testing 13 timing shifts, the strongest relationship was +0.784 (they moved in the same direction).
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
-0.301
15 periods · Return correlation when both series rose
Both Falling
+0.311
6 periods · Return correlation when both series fell
Diverging
-0.517
14 periods · Return correlation when series moved apart
R-Squared
61.1%
Share of variance in one series explained by the other.
Trend Agreement
67.8%
How often both series moved in the same direction period-to-period.
Overlap Quality
1,254
Deep shared window — 1,254 usable pairs.
Significance
p < 0.001
95% CI: [0.759, 0.802]
Scatter
XY Regression
Pipeline
Data quality details
Pipeline
Data quality details
Pipeline Summary
1,254 paired data points survived the daily window.
Raw input
1,254
1,254
Normalized
1,254
1,254
Prepared
1,254
1,254
Aligned
1,254
1,254
Invalid removed
0
A: 0 / B: 0
Duplicates removed
0
A: 0 / B: 0
Alignment drops
0
A: 0 / B: 0
Series A
BERKSHIRE HATHAWAY Class B
BRK.B
Market cap 1T
Stock · 1,254 raw → 1,254 prepared
Series B
Cummins Inc.
CMI
Market cap 76.3B · 67,400 employees
Stock · 1,254 raw → 1,254 prepared
Sign agreement
100.0%
How often both values share the same sign.
Zero crossings
32
Estimated crossover points between normalized spreads.
Slope
0.8747
Linear regression slope.
Intercept
-41.4523
Linear regression intercept.
Related Extremes
Highest and Lowest Correlated
Saved 6 hours ago · ID: stock-brk-b-vs-stock-cmi-daily