ASYS vs SPY: Correlation
Amtech Systems, Inc. (ASYS) and SPDR S&P 500 ETF Trust (SPY) show a weak relationship: their 3-year correlation of weekly returns is 0.18.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are ASYS and SPY?
On 3 years of weekly data the ASYS/SPY correlation comes out at 0.18, weak. The past 12 months show a tighter link (0.35) than the 3-year average (0.18). The 5-year figure is 0.28, and annualized covariance runs at 191.4 %².
SPY is close to the least connected end of ASYS's tracked universe, ranking #7 of 10. The last year tells two different stories: ASYS led by 144.6 percentage points, +165.2% for ASYS against +20.6% for SPY. Note the risk asymmetry: ASYS runs 5.0 times the annualized volatility of the other leg, so equal-weighting the two is not an equal-risk position.
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.
ASYS vs SPY: side by side
| ASYS (Amtech Systems, Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +165.2% | +20.6% |
| 5-year return | +54.0% | +82.4% |
| Volatility (ann.) | 71.9% | 14.5% |
| Beta vs S&P 500 | 0.92 | 1.00 |
| Max drawdown (3Y) | -61.3% | -18.8% |
| Market cap | $0.3B | – |
| P/E (trailing) | 56.5 | – |
| Dividend yield | 0.00% | 1.01% |
| Expense ratio | – | 0.09% |
| Assets under management | – | $795.3B |
| Sector / category | US Listed | ETF · US Large Cap |
SPY is a Large Blend fund from State Street Investment Management: $795.3B under management, 504 holdings, a 0.09% expense ratio, a 1.01% trailing dividend yield.
Year-by-year returns
| Year | ASYS | SPY |
|---|---|---|
| 2022 | -23.1% | -18.2% |
| 2023 | -44.7% | +26.2% |
| 2024 | +29.8% | +24.9% |
| 2025 | +130.3% | +17.7% |
| 2026 | +26.1% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are ASYS and SPY good diversifiers for each other?
By historical standards, yes. A correlation of 0.18 means the two rarely move for the same reasons.
FAQ
What is the correlation between ASYS and SPY?
Using weekly returns as of 2026-08-27: 0.18 over 3 years, with 0.35 over the last year and 0.28 over 5 years.
Is SPY a good diversifier for ASYS?
By historical standards, yes. A correlation of 0.18 means the two rarely move for the same reasons.
What does a correlation of 0.18 mean?
A reading of 0.18 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/asys-vs-spy.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/asys-vs-spy/)
Free with attribution; caching and terms are described in the API documentation.
Related comparisons
Hubs: ASYS correlations · SPY correlations
