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RNTX vs SPY: Correlation

How closely do Rein Therapeutics, Inc. (RNTX) and SPDR S&P 500 ETF Trust (SPY) trade together? Their weekly returns over three years give a correlation of 0.26, which is weak.

Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology

Correlation (3Y)
0.26
weak
Correlation (1Y)
0.17
last 12 months
Correlation (5Y)
0.24
long-run
Ann. covariance
372.8
%² · weekly, annualized

How correlated are RNTX and SPY?

Across a 3-year window, the weekly returns of RNTX and SPY correlate at 0.26, weak. Little has changed lately, as the 1-year reading of 0.17 lands near the 3-year figure. Stretching to 5 years gives 0.24, with an annualized covariance of 372.8 %².

Out of 11 assets tracked against RNTX, SPY lands near the bottom at #7. Their recent paths diverged sharply: over the last 12 months SPY outperformed by 49.4 percentage points (-28.8% for RNTX against +20.6% for SPY). One caveat on sizing: RNTX is 6.8 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.

RNTX vs SPY: side by side

RNTX (Rein Therapeutics, Inc.)SPY (SPDR S&P 500 ETF Trust)
1-year return-28.8%+20.6%
5-year return-96.4%+82.4%
Volatility (ann.)98.8%14.5%
Beta vs S&P 5001.781.00
Max drawdown (3Y)-89.7%-18.8%
Market cap$0.1B
P/E (trailing)
Dividend yield0.00%1.01%
Expense ratio0.09%
Assets under management$795.3B
Sector / categoryUS ListedETF · US Large Cap
Higher yield: SPY 1.01% vs 0.00%Smaller drawdown: SPY -18.8% vs -89.7%Higher 5y return: SPY +82.4% vs -96.4%

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.

-45%0%+32%2025-09-052026-08-27
Both assets over the last year, indexed to 100 at the starting week. RNTX · SPY

Year-by-year returns

YearRNTXSPY
2022-79.0%-18.2%
2023+28.6%+26.2%
2024-24.6%+24.9%
2025-49.6%+17.7%
2026-32.5%+13.7%

Calendar-year price returns; the current year is year-to-date as of the data date above.

Are RNTX and SPY good diversifiers for each other?

Yes, to a useful degree: a correlation of 0.26 leaves real independence between the two, which historically damped combined volatility.

FAQ

What is the correlation between RNTX and SPY?

Using weekly returns as of 2026-08-27: 0.26 over 3 years, with 0.17 over the last year and 0.24 over 5 years.

Is SPY a good diversifier for RNTX?

Yes, to a useful degree: a correlation of 0.26 leaves real independence between the two, which historically damped combined volatility.

What does a correlation of 0.26 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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RNTX vs SPY: 3-year weekly correlation 0.26RNTX vs SPY0.26

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Hubs: RNTX correlations · SPY correlations