Correlation Analysis
Costco Wholesale Corp vs Sandisk Corporation Common Stock
COST vs SNDK
+0.078
Weak 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
Sandisk Corporation Common Stock
↗SNDK
Sandisk is one of the five largest suppliers of NAND flash memory semiconductors globally. Sandisk is vertically integrated, producing substantially all of its flash chips at manufacturing sites across Japan via a joint-venture framework with Kioxia. Sandisk then repackages most of its chips into SSDs for consumer electronics, external storage, or cloud storage. Sandisk was formerly a piece of Western Digital for nine years (after being acquired in 2016) and was spun off as an independent company in 2025.
Market cap 107B · 11,000 employees
Time Series
Relative Performance
Who Moves First
SNDK leads COST by 6 days
SNDK tends to move before COST.
After testing 13 timing shifts, the strongest relationship was +0.123 (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
+0.296
10 periods · Return correlation when both series rose
Both Falling
N/A
4 periods · Return correlation when both series fell
Diverging
-0.369
21 periods · Return correlation when series moved apart
R-Squared
0.6%
Share of variance in one series explained by the other.
Trend Agreement
45.9%
How often both series moved in the same direction period-to-period.
Overlap Quality
281
Robust shared window — 281 usable pairs.
Significance
n.s.
95% CI: [-0.039, 0.193]
Scatter
XY Regression
Pipeline
Data quality details
Pipeline
Data quality details
Pipeline Summary
281 paired data points survived the daily window.
Raw input
1,254
281
Normalized
1,254
281
Prepared
1,254
281
Aligned
281
281
Invalid removed
0
A: 0 / B: 0
Duplicates removed
0
A: 0 / B: 0
Alignment drops
973
A: 973 / B: 0
Series A
Costco Wholesale Corp
COST
Market cap 451.9B
Stock · 1,254 raw → 1,254 prepared
Series B
Sandisk Corporation Common Stock
SNDK
Market cap 107B · 11,000 employees
Stock · 281 raw → 281 prepared
Sign agreement
100.0%
How often both values share the same sign.
Zero crossings
1
Estimated crossover points between normalized spreads.
Slope
0.3828
Linear regression slope.
Intercept
-162.2982
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
SNDK
Sandisk Corporation Common Stock
Highest
+0.964
Micron Technology, Inc.
MU · 281 data points
Lowest
-0.749
VISA Inc.
V · 281 data points
Saved 6 hours ago · ID: stock-cost-vs-stock-sndk-daily