MKTX vs SPY: Correlation
How closely do MarketAxess Holdings, Inc. (MKTX) and SPDR S&P 500 ETF Trust (SPY) trade together? Their weekly returns over three years give a correlation of 0.08, which is near-zero.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are MKTX and SPY?
Across a 3-year window, the weekly returns of MKTX and SPY correlate at 0.08, near zero, meaning they move largely independently. Recent behaviour matches the longer record: 0.10 over 1 year against 0.08 over 3. Stretching to 5 years gives 0.27, with an annualized covariance of 43.3 %².
Among the 14 assets we track against MKTX, SPY ranks #9 by 3-year correlation. Correlation aside, the last 12 months split them widely, with SPY ahead by 32.3 points (-11.7% versus +20.6%). One caveat on sizing: MKTX is 2.6 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.
MKTX vs SPY: side by side
| MKTX (MarketAxess Holdings, Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | -11.7% | +20.6% |
| 5-year return | -63.7% | +82.4% |
| Volatility (ann.) | 37.8% | 14.5% |
| Beta vs S&P 500 | 0.21 | 1.00 |
| Max drawdown (3Y) | -61.8% | -18.8% |
| Market cap | $5.7B | – |
| P/E (trailing) | 19.2 | – |
| Dividend yield | 1.90% | 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 | MKTX | SPY |
|---|---|---|
| 2022 | -31.5% | -18.2% |
| 2023 | +6.1% | +26.2% |
| 2024 | -21.8% | +24.9% |
| 2025 | -18.5% | +17.7% |
| 2026 | -9.0% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are MKTX and SPY good diversifiers for each other?
By historical standards, yes. A correlation of 0.08 means the two rarely move for the same reasons.
FAQ
What is the correlation between MKTX and SPY?
As of 2026-08-27, the correlation of weekly returns between MKTX and SPY is 0.08 over 3 years, 0.10 over 1 year and 0.27 over 5 years.
Is SPY a good diversifier for MKTX?
By historical standards, yes. A correlation of 0.08 means the two rarely move for the same reasons.
What does a correlation of 0.08 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.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/mktx-vs-spy.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/mktx-vs-spy/)
Free with attribution; caching and terms are described in the API documentation.
Related comparisons
Hubs: MKTX correlations · SPY correlations
