RDGT vs SPY: Correlation
How closely do Ridgetech, Inc. (RDGT) and SPDR S&P 500 ETF Trust (SPY) trade together? Their weekly returns over three years give a correlation of 0.03, which is near-zero.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are RDGT and SPY?
Over the past 3 years, RDGT and SPY moved with a correlation of 0.03, which is near zero, meaning they move largely independently. Recent behaviour matches the longer record: -0.02 over 1 year against 0.03 over 3. Over 5 years the correlation is 0.07, and the annualized covariance of weekly returns is 57.8 %².
Among the 21 assets we track against RDGT, SPY ranks #8 by 3-year correlation. Correlation aside, the last 12 months split them widely, with SPY ahead by 120.1 points (-99.5% versus +20.6%). One caveat on sizing: RDGT is 8.3 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.
RDGT vs SPY: side by side
| RDGT (Ridgetech, Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | -99.5% | +20.6% |
| 5-year return | -100.0% | +82.4% |
| Volatility (ann.) | 120.7% | 14.5% |
| Beta vs S&P 500 | 0.28 | 1.00 |
| Max drawdown (3Y) | -99.9% | -18.8% |
| Market cap | – | – |
| P/E (trailing) | – | – |
| 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 | RDGT | SPY |
|---|---|---|
| 2022 | -21.5% | -18.2% |
| 2023 | -93.9% | +26.2% |
| 2024 | -59.8% | +24.9% |
| 2025 | +61.0% | +17.7% |
| 2026 | -99.8% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are RDGT and SPY good diversifiers for each other?
Yes. With a correlation of 0.03, RDGT and SPY have moved largely independently, which makes them a genuinely diversifying pair by historical standards.
FAQ
What is the correlation between RDGT and SPY?
The RDGT/SPY correlation stands at 0.03 on a 3-year window (1 year: -0.02, 5 years: 0.07), computed from weekly returns as of 2026-08-27.
Is SPY a good diversifier for RDGT?
Yes. With a correlation of 0.03, RDGT and SPY have moved largely independently, which makes them a genuinely diversifying pair by historical standards.
What does a correlation of 0.03 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: RDGT correlations · SPY correlations
