Correlation Analysis
Costco Wholesale Corp vs Merck & Co., Inc.
COST vs MRK
+0.211
Light 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
Merck & Co., Inc.
↗MRK
Merck makes pharmaceutical products to treat several conditions in a number of therapeutic areas, including cardiometabolic disease, cancer, and infections. Within cancer, the firm's immuno-oncology platform, led by Keytruda, is a major contributor to overall sales. The company also has a substantial vaccine business aimed at preventing pediatric diseases, as well as Gardasil for human papillomavirus. Additionally, Merck sells animal health-related drugs. From a geographical perspective, 47% of the company's sales are generated from US human health (pharmaceuticals and vaccines).
Market cap 298.8B
Time Series
Relative Performance
Who Moves First
MRK leads COST by 6 days
MRK tends to move before COST.
After testing 13 timing shifts, the strongest relationship was +0.212 (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
+0.469
9 periods · Return correlation when both series rose
Both Falling
N/A
3 periods · Return correlation when both series fell
Diverging
-0.798
23 periods · Return correlation when series moved apart
R-Squared
4.4%
Share of variance in one series explained by the other.
Trend Agreement
55.1%
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: [0.157, 0.263]
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
Merck & Co., Inc.
MRK
Market cap 298.8B
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
0.0165
Linear regression slope.
Intercept
86.9951
Linear regression intercept.
Related Extremes
Highest and Lowest Correlated
Saved 9 hours ago · ID: stock-cost-vs-stock-mrk-daily