BLIN vs COST: Correlation
Measured on weekly returns over the past three years, Bridgeline Digital, Inc. (BLIN) and Costco (COST) carry a correlation of -0.20, a negative link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are BLIN and COST?
Over the past 3 years, BLIN and COST moved with a correlation of -0.20, which is negative, meaning they tend to move in opposite directions. Lately the two have drifted apart, with the 1-year correlation at -0.34 versus -0.20 over 3 years. Over 5 years the correlation is 0.05, and the annualized covariance of weekly returns is -236.0 %².
Out of 10 assets tracked against BLIN, COST lands near the bottom at #9. The last year tells two different stories: COST led by 25.9 percentage points, -26.9% for BLIN against -1.0% for COST. One caveat on sizing: BLIN is 3.0 times as volatile as the other leg, so an equal-dollar split is far from equal-risk.
How is this computed?
Pearson correlation on weekly returns: ρ(A,B) = cov(rA, rB) / (σA · σB), over windows of 52, 156 and 260 weeks. Covariance is annualized (×52) and expressed in %². Full definitions on the methodology page.
BLIN vs COST: side by side
| BLIN (Bridgeline Digital, Inc.) | COST (Costco) | |
|---|---|---|
| 1-year return | -26.9% | -1.0% |
| 5-year return | -81.9% | +116.3% |
| Volatility (ann.) | 60.1% | 19.8% |
| Beta vs S&P 500 | 0.36 | 0.45 |
| Max drawdown (3Y) | -70.2% | -20.7% |
| Market cap | – | $414.5B |
| P/E (trailing) | – | 48.1 |
| Dividend yield | 0.00% | 0.56% |
| Sector / category | US Listed | Consumer Staples |
Year-by-year returns
| Year | BLIN | COST |
|---|---|---|
| 2022 | -53.5% | -19.0% |
| 2023 | -17.1% | +49.0% |
| 2024 | +81.6% | +39.6% |
| 2025 | -47.5% | -5.4% |
| 2026 | +19.0% | +8.9% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are BLIN and COST good diversifiers for each other?
By historical standards, yes. A correlation of -0.20 means the two rarely move for the same reasons.
FAQ
What is the correlation between BLIN and COST?
As of 2026-08-27, the correlation of weekly returns between BLIN and COST is -0.20 over 3 years, -0.34 over 1 year and 0.05 over 5 years.
Is COST a good diversifier for BLIN?
By historical standards, yes. A correlation of -0.20 means the two rarely move for the same reasons.
What does a correlation of -0.20 mean?
Correlation ranges from −1 to +1. Values near +1 mean two assets move together, near 0 that they move independently, and negative values that they tend to move in opposite directions. It measures co-movement, not performance.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/blin-vs-cost.json
Markdown for the live badge, attribution link included:
[](https://www.pairbook.io/pair/blin-vs-cost/)
Free with attribution; caching and terms are described in the API documentation.
Related comparisons
Hubs: BLIN correlations · COST correlations
