PROK vs SPY: Correlation
How closely do ProKidney Corp. - Class A (PROK) and SPDR S&P 500 ETF Trust (SPY) trade together? Their weekly returns over three years give a correlation of 0.09, which is near-zero.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are PROK and SPY?
Across a 3-year window, the weekly returns of PROK and SPY correlate at 0.09, near zero, meaning they move largely independently. Lately the two have moved closer together, with the 1-year correlation at 0.37 versus 0.09 over 3 years. Stretching to 5 years gives 0.07, with an annualized covariance of 460.7 %².
SPY is close to the least connected end of PROK's tracked universe, ranking #17 of 21. The last year tells two different stories: SPY led by 47.5 percentage points, -26.9% for PROK against +20.6% for SPY. Risk is not evenly split, since PROK carries 25.4 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.
PROK vs SPY: side by side
| PROK (ProKidney Corp. - Class A) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | -26.9% | +20.6% |
| 5-year return | -81.3% | +82.4% |
| Volatility (ann.) | 368.1% | 14.5% |
| Beta vs S&P 500 | 2.21 | 1.00 |
| Max drawdown (3Y) | -94.3% | -18.8% |
| Market cap | $0.7B | – |
| 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 | PROK | SPY |
|---|---|---|
| 2022 | -30.7% | -18.2% |
| 2023 | -74.1% | +26.2% |
| 2024 | -5.1% | +24.9% |
| 2025 | +32.5% | +17.7% |
| 2026 | -18.7% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are PROK and SPY good diversifiers for each other?
Yes: at 0.09, the two have gone their own ways historically, which is what genuine diversification looks like.
FAQ
What is the correlation between PROK and SPY?
As of 2026-08-27, the correlation of weekly returns between PROK and SPY is 0.09 over 3 years, 0.37 over 1 year and 0.07 over 5 years.
Is SPY a good diversifier for PROK?
Yes: at 0.09, the two have gone their own ways historically, which is what genuine diversification looks like.
What does a correlation of 0.09 mean?
On the −1 to +1 scale, 0.09 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.
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Related comparisons
Hubs: PROK correlations · SPY correlations
