Correlation Analysis
Costco Wholesale Corp vs Steel Dynamics Inc
COST vs STLD
+0.809
Strong positive
When one moves up, the other tends to follow.
Costco Wholesale Corp
↗COST
Founded in 1983, Costco Wholesale now operates a global chain of membership-based warehouse clubs, delivering high-quality goods and services at consistently low prices. As of its most recent fiscal year, Costco operated approximately 910 warehouses, serving more than 80 million members across its three geographic segments: Costco US (approximately 73% of total revenue), Costco Canada (13%), and Costco International (14%).Costco's core value proposition—quality products at unbeatable prices—has yielded consistently strong member renewal rates (93% in the US and Canada and nearly 90% internationally). About 55% of Costco's fiscal 2025 revenue came from its grocery offerings, and another 25% from general merchandise.
Market cap 451.9B
Steel Dynamics Inc
↗STLD
Steel Dynamics Inc operates as a domestic steel producer and metal recycler in the United States. The company's product portfolio comprises hot rolled sheet, hot rolled plate, painted sheet products, cold rolled sheet, and others. Its reportable segments are steel operations, metals recycling operations, steel fabrication operations, and aluminum operations. Maximum revenue is generated from its steel operations segment, which consists of manufacturing various steel products and numerous coating operations. Its primary sources of revenue are currently from the manufacture and sale of steel products, the processing and sale of recycled ferrous and nonferrous metals, and the fabrication and sale of steel joists and deck products.
Market cap 25.5B · 14,400 employees
Time Series
Relative Performance
Who Moves First
in sync
COST and STLD tend to move at the same time.
After testing 13 timing shifts, the strongest relationship was +0.809 (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
+0.490
10 periods · Return correlation when both series rose
Both Falling
N/A
2 periods · Return correlation when both series fell
Diverging
-0.587
23 periods · Return correlation when series moved apart
R-Squared
65.5%
Share of variance in one series explained by the other.
Trend Agreement
57.3%
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: [0.789, 0.828]
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
Costco Wholesale Corp
COST
Market cap 451.9B
Stock · 1,254 raw → 1,254 prepared
Series B
Steel Dynamics Inc
STLD
Market cap 25.5B · 14,400 employees
Stock · 1,254 raw → 1,254 prepared
Sign agreement
100.0%
How often both values share the same sign.
Zero crossings
7
Estimated crossover points between normalized spreads.
Slope
0.1271
Linear regression slope.
Intercept
22.4961
Linear regression intercept.
Related Extremes
Highest and Lowest Correlated
Saved 9 hours ago · ID: stock-cost-vs-stock-stld-daily