SPY vs SY: Correlation
How closely do SPDR S&P 500 ETF Trust (SPY) and So-Young International Inc. - American Depository Shares (SY) trade together? Their weekly returns over three years give a correlation of 0.16, which is weak.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are SPY and SY?
Across a 3-year window, the weekly returns of SPY and SY correlate at 0.16, weak. Lately the two have drifted apart, with the 1-year correlation at 0.01 versus 0.16 over 3 years. Stretching to 5 years gives 0.18, with an annualized covariance of 225.9 %².
Within SPY's tracked universe of 4755 assets, SY comes in at #3647 by 3-year correlation. The last year tells two different stories: SPY led by 61.6 percentage points, +20.6% for SPY against -41.0% for SY. Risk is not evenly split, since SY carries 6.9 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.
SPY vs SY: side by side
| SPY (SPDR S&P 500 ETF Trust) | SY (So-Young International Inc. - American Depository Shares) | |
|---|---|---|
| 1-year return | +20.6% | -41.0% |
| 5-year return | +82.4% | -54.5% |
| Volatility (ann.) | 14.5% | 99.6% |
| Beta vs S&P 500 | 1.00 | 1.08 |
| Max drawdown (3Y) | -18.8% | -77.5% |
| Market cap | – | $0.2B |
| P/E (trailing) | – | – |
| Dividend yield | 1.01% | 0.00% |
| Expense ratio | 0.09% | – |
| Assets under management | $795.3B | – |
| Sector / category | ETF · US Large Cap | US Listed |
SPY, State Street Investment Management's Large Blend fund, carries $795.3B under management, 504 holdings, a 0.09% expense ratio, a 1.01% trailing dividend yield.
Year-by-year returns
| Year | SPY | SY |
|---|---|---|
| 2022 | -18.2% | -59.6% |
| 2023 | +26.2% | +0.0% |
| 2024 | +24.9% | -32.1% |
| 2025 | +17.7% | +219.0% |
| 2026 | +13.7% | -9.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are SPY and SY good diversifiers for each other?
Yes. With a correlation of 0.16, SPY and SY have moved largely independently, which makes them a genuinely diversifying pair by historical standards.
FAQ
What is the correlation between SPY and SY?
The SPY/SY correlation stands at 0.16 on a 3-year window (1 year: 0.01, 5 years: 0.18), computed from weekly returns as of 2026-08-27.
Is SY a good diversifier for SPY?
Yes. With a correlation of 0.16, SPY and SY have moved largely independently, which makes them a genuinely diversifying pair by historical standards.
What does a correlation of 0.16 mean?
On the −1 to +1 scale, 0.16 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.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/spy-vs-sy.json
Drop this badge in a README or notebook; it updates with the data:
[](https://www.pairbook.io/pair/spy-vs-sy/)
No key needed, free to use. Full endpoint list in the API documentation.
Related comparisons
Hubs: SPY correlations · SY correlations
