BIRD vs EFOI: Correlation
Smartbird, Inc. (BIRD) and Energy Focus, Inc. (EFOI) show a strong relationship: their 3-year correlation of weekly returns is 0.77.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are BIRD and EFOI?
Over the past 3 years, BIRD and EFOI moved with a correlation of 0.77, which is strong. The past 12 months show a tighter link (0.93) than the 3-year average (0.77). Over 5 years the correlation is 0.64, and the annualized covariance of weekly returns is 27725.4 %².
EFOI is one of the assets that tracks BIRD most closely: it ranks #2 out of the 17 assets we track against BIRD. The last year tells two different stories: EFOI led by 64.6 percentage points, -51.4% for BIRD against +13.2% for EFOI.
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.
BIRD vs EFOI: side by side
| BIRD (Smartbird, Inc.) | EFOI (Energy Focus, Inc.) | |
|---|---|---|
| 1-year return | -51.4% | +13.2% |
| 5-year return | -99.5% | -87.5% |
| Volatility (ann.) | 225.6% | 158.7% |
| Beta vs S&P 500 | 3.94 | 1.96 |
| Max drawdown (3Y) | -92.3% | -58.2% |
| Market cap | – | – |
| P/E (trailing) | – | – |
| Dividend yield | 0.00% | 0.00% |
| Sector / category | US Listed | US Listed |
Year-by-year returns
| Year | BIRD | EFOI |
|---|---|---|
| 2022 | -84.0% | -92.5% |
| 2023 | -49.4% | -32.6% |
| 2024 | -71.6% | -21.2% |
| 2025 | -41.2% | +94.1% |
| 2026 | -22.7% | +25.5% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are BIRD and EFOI good diversifiers for each other?
Only partially. A correlation of 0.77 means BIRD and EFOI share most of their swings. Pairing them dampens volatility somewhat, but it will not protect against a common drawdown.
FAQ
What is the correlation between BIRD and EFOI?
Using weekly returns as of 2026-08-27: 0.77 over 3 years, with 0.93 over the last year and 0.64 over 5 years.
Is EFOI a good diversifier for BIRD?
Only partially. A correlation of 0.77 means BIRD and EFOI share most of their swings. Pairing them dampens volatility somewhat, but it will not protect against a common drawdown.
What does a correlation of 0.77 mean?
On the −1 to +1 scale, 0.77 describes how much the two returns move together: +1 is lockstep, 0 is independence, negative values mean opposite directions. It says nothing about which performed better.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/bird-vs-efoi.json
Markdown for the live badge, attribution link included:
[](https://www.pairbook.io/pair/bird-vs-efoi/)
Free with attribution; caching and terms are described in the API documentation.
Related comparisons
Hubs: BIRD correlations · EFOI correlations
