OTTR vs SPY: Correlation
How closely do Otter Tail Corporation (OTTR) and SPDR S&P 500 ETF Trust (SPY) trade together? Their weekly returns over three years give a correlation of 0.31, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are OTTR and SPY?
Across a 3-year window, the weekly returns of OTTR and SPY correlate at 0.31, moderate. The link has loosened recently: the 1-year correlation (0.02) runs below the 3-year figure (0.31). Stretching to 5 years gives 0.35, with an annualized covariance of 119.0 %².
SPY is close to the least connected end of OTTR's tracked universe, ranking #6 of 10. On 12-month performance SPY holds a 9.9-point edge, +10.7% against +20.6%. Note the risk asymmetry: OTTR runs 1.8 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.
OTTR vs SPY: side by side
| OTTR (Otter Tail Corporation) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +10.7% | +20.6% |
| 5-year return | +88.2% | +82.4% |
| Volatility (ann.) | 26.7% | 14.5% |
| Beta vs S&P 500 | 0.57 | 1.00 |
| Max drawdown (3Y) | -27.1% | -18.8% |
| Market cap | $3.8B | – |
| P/E (trailing) | 19.9 | – |
| Dividend yield | 2.39% | 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 | OTTR | SPY |
|---|---|---|
| 2022 | -15.6% | -18.2% |
| 2023 | +48.1% | +26.2% |
| 2024 | -11.2% | +24.9% |
| 2025 | +12.3% | +17.7% |
| 2026 | +15.7% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are OTTR and SPY good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.31 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between OTTR and SPY?
As of 2026-08-27, the correlation of weekly returns between OTTR and SPY is 0.31 over 3 years, 0.02 over 1 year and 0.35 over 5 years.
Is SPY a good diversifier for OTTR?
Yes, to a useful degree: a correlation of 0.31 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.31 mean?
A reading of 0.31 sits on a scale from −1 (opposite moves) through 0 (unrelated) to +1 (identical moves). Correlation captures direction, not magnitude or performance.
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Related comparisons
Hubs: OTTR correlations · SPY correlations
