BLDP vs PLUG: Correlation
How closely do Ballard Power Systems, Inc. (BLDP) and Plug Power, Inc. (PLUG) trade together? Their weekly returns over three years give a correlation of 0.65, which is strong.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are BLDP and PLUG?
Over the past 3 years, BLDP and PLUG moved with a correlation of 0.65, which is strong. Little has changed lately, as the 1-year reading of 0.68 lands near the 3-year figure. Over 5 years the correlation is 0.70, and the annualized covariance of weekly returns is 4246.5 %².
Few assets follow BLDP as closely as PLUG, which ranks #2 of 23 tracked partners. Correlation aside, the last 12 months split them widely, with PLUG ahead by 24.3 points (+15.8% versus +40.1%).
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.
BLDP vs PLUG: side by side
| BLDP (Ballard Power Systems, Inc.) | PLUG (Plug Power, Inc.) | |
|---|---|---|
| 1-year return | +15.8% | +40.1% |
| 5-year return | -85.8% | -91.3% |
| Volatility (ann.) | 66.3% | 98.9% |
| Beta vs S&P 500 | 1.62 | 1.49 |
| Max drawdown (3Y) | -76.4% | -92.1% |
| Market cap | $0.7B | $3.2B |
| P/E (trailing) | – | – |
| Dividend yield | 0.00% | 0.00% |
| Sector / category | US Listed | US Listed |
Year-by-year returns
| Year | BLDP | PLUG |
|---|---|---|
| 2022 | -61.9% | -56.2% |
| 2023 | -22.8% | -63.6% |
| 2024 | -55.1% | -52.7% |
| 2025 | +53.0% | -7.5% |
| 2026 | -7.9% | +15.2% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are BLDP and PLUG good diversifiers for each other?
Somewhat, no more. With 0.65 correlation, most large moves hit both names, and the diversification benefit stays modest.
FAQ
What is the correlation between BLDP and PLUG?
As of 2026-08-27, the correlation of weekly returns between BLDP and PLUG is 0.65 over 3 years, 0.68 over 1 year and 0.70 over 5 years.
Is PLUG a good diversifier for BLDP?
Somewhat, no more. With 0.65 correlation, most large moves hit both names, and the diversification benefit stays modest.
What does a correlation of 0.65 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.
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Related comparisons
Hubs: BLDP correlations · PLUG correlations
