Correlation Analysis
Alcoa Corporation vs Costco Wholesale Corp
AA vs COST
-0.213
Light inverse
When one moves up, the other tends to move down.
Alcoa Corporation
↗AA
Alcoa is a vertically integrated aluminum company whose operations include bauxite mining, alumina refining, and manufacturing primary aluminum. It is one of the world's largest bauxite miners and alumina refiners by production volume, but sits outside the top-10 aluminum producers, a list dominated by Chinese companies. Profits are closely tied to prevailing commodity prices along the aluminum supply chain.Alcoa was the first mass producer of aluminum, launching the world-changing Hall-Heroult smelting process in the 1880s, making aluminum affordable. It listed as a public company in 1925. In 2016, Alcoa spun off its automotive and aerospace metal parts segment to focus on mining, smelting, and refining. It bought the 40% unowned balance of AWAC in mid-2024.
Market cap 18.7B · 14,900 employees
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
Time Series
Relative Performance
Who Moves First
AA leads COST by 6 days
AA tends to move before COST.
After testing 13 timing shifts, the strongest relationship was -0.236 (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
-0.252
11 periods · Return correlation when both series rose
Both Falling
+0.595
5 periods · Return correlation when both series fell
Diverging
-0.660
19 periods · Return correlation when series moved apart
R-Squared
4.6%
Share of variance in one series explained by the other.
Trend Agreement
54.1%
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: [-0.266, -0.160]
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
Alcoa Corporation
AA
Market cap 18.7B · 14,900 employees
Stock · 1,254 raw → 1,254 prepared
Series B
Costco Wholesale Corp
COST
Market cap 451.9B
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
-3.4163
Linear regression slope.
Intercept
825.7635
Linear regression intercept.
Related Extremes
Highest and Lowest Correlated
Saved 7 hours ago · ID: stock-aa-vs-stock-cost-daily