RFAI vs ZSTK: Correlation
RF Acquisition Corp II (RFAI) and ZeroStack Corp. (ZSTK) show a strong relationship: their 3-year correlation of weekly returns is 0.63.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are RFAI and ZSTK?
Across a 3-year window, the weekly returns of RFAI and ZSTK correlate at 0.63, strong. Recent behaviour matches the longer record: 0.72 over 1 year against 0.63 over 3. Stretching to 5 years gives n/a, with an annualized covariance of 28147.1 %².
ZSTK is one of the assets that tracks RFAI most closely: it ranks #3 out of the 65 assets we track against RFAI. Correlation aside, the last 12 months split them widely, with RFAI ahead by 462.9 points (+389.5% versus -73.4%). One caveat on sizing: RFAI is 1.9 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.
RFAI vs ZSTK: side by side
| RFAI (RF Acquisition Corp II) | ZSTK (ZeroStack Corp.) | |
|---|---|---|
| 1-year return | +389.5% | -73.4% |
| 5-year return | n/a | -99.9% |
| Volatility (ann.) | 288.3% | 153.8% |
| Beta vs S&P 500 | -1.62 | 2.10 |
| Max drawdown (3Y) | -16.5% | -99.1% |
| Market cap | $0.4B | $0.1B |
| P/E (trailing) | 399.9 | – |
| Dividend yield | 0.00% | 0.00% |
| Sector / category | US Listed | US Listed |
Year-by-year returns
| Year | RFAI | ZSTK |
|---|---|---|
| 2022 | – | -87.2% |
| 2023 | – | -70.4% |
| 2024 | – | -23.7% |
| 2025 | +5.2% | -84.4% |
| 2026 | +383.6% | -6.1% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are RFAI and ZSTK good diversifiers for each other?
Only partially. A correlation of 0.63 means RFAI and ZSTK 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 RFAI and ZSTK?
As of 2026-08-27, the correlation of weekly returns between RFAI and ZSTK is 0.63 over 3 years, 0.72 over 1 year and n/a over 5 years.
Is ZSTK a good diversifier for RFAI?
Only partially. A correlation of 0.63 means RFAI and ZSTK share most of their swings. Pairing them dampens volatility somewhat, but it will not protect against a common drawdown.
What does a correlation of 0.63 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/rfai-vs-zstk.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/rfai-vs-zstk/)
The core API is free. Terms and every endpoint in the API documentation.
Related comparisons
Hubs: RFAI correlations · ZSTK correlations
