BLDP vs TAN: Correlation
Measured on weekly returns over the past three years, Ballard Power Systems, Inc. (BLDP) and Invesco Solar ETF (TAN) carry a correlation of 0.59, a moderate link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are BLDP and TAN?
Across a 3-year window, the weekly returns of BLDP and TAN correlate at 0.59, moderate. The relationship has been stable: the 1-year correlation (0.51) sits close to the 3-year figure. Stretching to 5 years gives 0.66, with an annualized covariance of 1461.6 %².
Few assets follow BLDP as closely as TAN, which ranks #3 of 23 tracked partners. On 12-month performance TAN holds a 5.6-point edge, +15.8% against +21.4%. Risk is not evenly split, since BLDP carries 1.8 times the volatility of the other side.
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 TAN: side by side
| BLDP (Ballard Power Systems, Inc.) | TAN (Invesco Solar ETF) | |
|---|---|---|
| 1-year return | +15.8% | +21.4% |
| 5-year return | -85.8% | -41.9% |
| Volatility (ann.) | 66.3% | 37.4% |
| Beta vs S&P 500 | 1.62 | 1.04 |
| Max drawdown (3Y) | -76.4% | -55.4% |
| Market cap | $0.7B | – |
| P/E (trailing) | – | – |
| Dividend yield | 0.00% | – |
| Sector / category | US Listed | ETF · Thematic |
Year-by-year returns
| Year | BLDP | TAN |
|---|---|---|
| 2022 | -61.9% | -5.2% |
| 2023 | -22.8% | -26.8% |
| 2024 | -55.1% | -37.6% |
| 2025 | +53.0% | +48.3% |
| 2026 | -7.9% | +1.3% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are BLDP and TAN good diversifiers for each other?
Somewhat, no more. With 0.59 correlation, most large moves hit both names, and the diversification benefit stays modest.
FAQ
What is the correlation between BLDP and TAN?
The BLDP/TAN correlation stands at 0.59 on a 3-year window (1 year: 0.51, 5 years: 0.66), computed from weekly returns as of 2026-08-27.
Is TAN a good diversifier for BLDP?
Somewhat, no more. With 0.59 correlation, most large moves hit both names, and the diversification benefit stays modest.
What does a correlation of 0.59 mean?
A reading of 0.59 sits on a scale from −1 (opposite moves) through 0 (unrelated) to +1 (identical moves). Correlation captures direction, not magnitude or performance.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/bldp-vs-tan.json
Markdown for the live badge, attribution link included:
[](https://www.pairbook.io/pair/bldp-vs-tan/)
No key needed, free to use. Full endpoint list in the API documentation.
Related comparisons
Hubs: BLDP correlations · TAN correlations
