ATEN vs MDY: Correlation
How closely do A10 Networks, Inc. (ATEN) and SPDR S&P MidCap 400 ETF (MDY) trade together? Their weekly returns over three years give a correlation of 0.45, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are ATEN and MDY?
Across a 3-year window, the weekly returns of ATEN and MDY correlate at 0.45, moderate. Lately the two have drifted apart, with the 1-year correlation at 0.27 versus 0.45 over 3 years. Stretching to 5 years gives 0.42, with an annualized covariance of 254.3 %².
Within ATEN's tracked universe of 14 assets, MDY comes in at #5 by 3-year correlation. The last year tells two different stories: ATEN led by 38.3 percentage points, +56.6% for ATEN against +18.3% for MDY. Risk is not evenly split, since ATEN carries 2.1 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.
ATEN vs MDY: side by side
| ATEN (A10 Networks, Inc.) | MDY (SPDR S&P MidCap 400 ETF) | |
|---|---|---|
| 1-year return | +56.6% | +18.3% |
| 5-year return | +106.4% | +47.5% |
| Volatility (ann.) | 34.0% | 16.5% |
| Beta vs S&P 500 | 0.89 | 0.91 |
| Max drawdown (3Y) | -33.9% | -24.0% |
| Market cap | $2.0B | – |
| P/E (trailing) | 44.3 | – |
| Dividend yield | 0.93% | 1.02% |
| Expense ratio | – | 0.23% |
| Assets under management | – | $26.5B |
| Sector / category | US Listed | ETF · US Small & Mid Cap |
MDY, State Street Investment Management's Mid-Cap Blend fund, carries $26.5B under management, 400 holdings, a 0.23% expense ratio, a 1.02% trailing dividend yield.
Year-by-year returns
| Year | ATEN | MDY |
|---|---|---|
| 2022 | +1.7% | -13.3% |
| 2023 | -19.4% | +16.1% |
| 2024 | +42.1% | +13.6% |
| 2025 | -2.6% | +7.2% |
| 2026 | +53.9% | +16.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are ATEN and MDY good diversifiers for each other?
A fair diversifier. At 0.45, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
FAQ
What is the correlation between ATEN and MDY?
The ATEN/MDY correlation stands at 0.45 on a 3-year window (1 year: 0.27, 5 years: 0.42), computed from weekly returns as of 2026-08-27.
Is MDY a good diversifier for ATEN?
A fair diversifier. At 0.45, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
What does a correlation of 0.45 mean?
On the −1 to +1 scale, 0.45 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/aten-vs-mdy.json
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Related comparisons
Hubs: ATEN correlations · MDY correlations
