Correlation Analysis
Apple Inc. vs West Pharmaceutical Services, Inc.
AAPL vs WST
-0.392
Light inverse
When one moves up, the other tends to move down.
Apple Inc.
↗AAPL
Apple is among the largest companies in the world, with a broad portfolio of hardware and software products targeted at consumers and businesses. Apple's iPhone makes up a majority of the firm sales, and Apple's other products like Mac, iPad, and Watch are designed around the iPhone as the focal point of an expansive software ecosystem. Apple has progressively worked to add new applications, like streaming video, subscription bundles, and augmented reality. The firm designs its own software and semiconductors while working with subcontractors like Foxconn and TSMC to build its products and chips. Slightly less than half of Apple's sales come directly through its flagship stores, with a majority of sales coming indirectly through partnerships and distribution.
Market cap 3.8T
West Pharmaceutical Services, Inc.
↗WST
West Pharmaceutical Services is based in Pennsylvania and is a key supplier to firms in the pharmaceutical, biotechnology, and generic drug industries. West sells elastomer-based packaging components (including stoppers, seals, and plungers), nonglass containment solutions, and auto-injectors for injectable drugs, which include large-molecule biologics, peptides such as GLP-1 receptor agonists, and small-molecule drugs. The company reports in two segments: proprietary products (about 80% of total revenue) and contract-manufactured products (about 20% of total revenue). It generates approximately 55% of its revenue from international markets and 45% from the United States.
Market cap 18.5B · 10,800 employees
Time Series
Relative Performance
Who Moves First
AAPL leads WST by 6 days
AAPL tends to move before WST.
After testing 13 timing shifts, the strongest relationship was -0.409 (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
-0.249
14 periods · Return correlation when both series rose
Both Falling
+0.252
9 periods · Return correlation when both series fell
Diverging
-0.458
12 periods · Return correlation when series moved apart
R-Squared
15.4%
Share of variance in one series explained by the other.
Trend Agreement
60.7%
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: [-0.438, -0.344]
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
Apple Inc.
AAPL
Market cap 3.8T
Stock · 1,254 raw → 1,254 prepared
Series B
West Pharmaceutical Services, Inc.
WST
Market cap 18.5B · 10,800 employees
Stock · 1,254 raw → 1,254 prepared
Sign agreement
100.0%
How often both values share the same sign.
Zero crossings
5
Estimated crossover points between normalized spreads.
Slope
-0.6258
Linear regression slope.
Intercept
439.5239
Linear regression intercept.
Related Extremes
Highest and Lowest Correlated
AAPL
Apple Inc.
Highest
+0.935
Arista Networks
ANET · 1,254 data points
Lowest
-0.847
Fiserv, Inc. Common Stock
FISV · 644 data points
WST
West Pharmaceutical Services, Inc.
Highest
-0.168
Tesla, Inc. Common Stock
TSLA · 1,254 data points
Lowest
-0.580
Walmart Inc. Common Stock
WMT · 1,254 data points
Saved 5 hours ago · ID: stock-aapl-vs-stock-wst-daily-20260408-xiqon2