Correlation Analysis
Costco Wholesale Corp vs Medline Inc. Class A common stock
COST vs MDLN
+0.502
Moderate 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
Medline Inc. Class A common stock
↗MDLN
Medline is the largest medical-surgical products and supply chain solutions provider in the US. The company generates over 90% of its revenue domestically and serves some of the largest US health systems. Medline offers approximately 190,000 Medline-branded products across more than 250 product families—including front line care, surgical solutions, and laboratory and diagnostics—as well as roughly 150,000 third-party products sourced from over 1,250 vendors. The company maintains prime vendor relationships with many customers, acting as the primary consolidated logistics partner for their medical-surgical needs. Medline has significant scale, supported by more than 30 manufacturing facilities and a fleet of over 2,000 owned delivery trucks. Medline went public in December 2025.
Market cap 35.6B · 45,000 employees
Time Series
Relative Performance
Who Moves First
in sync
COST and MDLN tend to move at the same time.
After testing 13 timing shifts, the strongest relationship was +0.502 (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
-0.365
10 periods · Return correlation when both series rose
Both Falling
+0.303
5 periods · Return correlation when both series fell
Diverging
-0.528
20 periods · Return correlation when series moved apart
R-Squared
25.2%
Share of variance in one series explained by the other.
Trend Agreement
47.3%
How often both series moved in the same direction period-to-period.
Overlap Quality
75
Thin shared window — 75 usable pairs.
Significance
p < 0.001
95% CI: [0.311, 0.655]
Scatter
XY Regression
Pipeline
Data quality details
Pipeline
Data quality details
Pipeline Summary
75 paired data points survived the daily window.
Raw input
1,254
75
Normalized
1,254
75
Prepared
1,254
75
Aligned
75
75
Invalid removed
0
A: 0 / B: 0
Duplicates removed
0
A: 0 / B: 0
Alignment drops
1,179
A: 1179 / B: 0
Series A
Costco Wholesale Corp
COST
Market cap 451.9B
Stock · 1,254 raw → 1,254 prepared
Series B
Medline Inc. Class A common stock
MDLN
Market cap 35.6B · 45,000 employees
Stock · 75 raw → 75 prepared
Sign agreement
100.0%
How often both values share the same sign.
Zero crossings
3
Estimated crossover points between normalized spreads.
Slope
0.0241
Linear regression slope.
Intercept
20.7495
Linear regression intercept.
Related Extremes
Highest and Lowest Correlated
COST
Costco Wholesale Corp
Highest
+0.977
Republic Services Inc.
RSG · 1,254 data points
Lowest
-0.912
Fiserv, Inc. Common Stock
FISV · 644 data points
MDLN
Medline Inc. Class A common stock
Highest
+0.529
Johnson & Johnson
JNJ · 75 data points
Lowest
-0.600
NetFlix Inc
NFLX · 75 data points
Saved 7 hours ago · ID: stock-cost-vs-stock-mdln-daily