CTS vs MDY: Correlation
How closely do CTS Corporation (CTS) and SPDR S&P MidCap 400 ETF (MDY) trade together? Their weekly returns over three years give a correlation of 0.74, which is strong.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are CTS and MDY?
Over the past 3 years, CTS and MDY moved with a correlation of 0.74, which is strong. Lately the two have drifted apart, with the 1-year correlation at 0.63 versus 0.74 over 3 years. Over 5 years the correlation is 0.61, and the annualized covariance of weekly returns is 403.8 %².
MDY is one of the assets that tracks CTS most closely: it ranks #1 out of the 26 assets we track against CTS. Their recent paths diverged sharply: over the last 12 months CTS outperformed by 17.5 percentage points (+35.8% for CTS against +18.3% for MDY). Risk is not evenly split, since CTS carries 2.0 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.
CTS vs MDY: side by side
| CTS (CTS Corporation) | MDY (SPDR S&P MidCap 400 ETF) | |
|---|---|---|
| 1-year return | +35.8% | +18.3% |
| 5-year return | +63.4% | +47.5% |
| Volatility (ann.) | 33.0% | 16.5% |
| Beta vs S&P 500 | 1.40 | 0.91 |
| Max drawdown (3Y) | -40.6% | -24.0% |
| Market cap | $1.6B | – |
| P/E (trailing) | 23.8 | – |
| Dividend yield | 0.28% | 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 | CTS | MDY |
|---|---|---|
| 2022 | +7.8% | -13.3% |
| 2023 | +11.4% | +16.1% |
| 2024 | +20.9% | +13.6% |
| 2025 | -18.4% | +7.2% |
| 2026 | +34.7% | +16.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are CTS and MDY good diversifiers for each other?
To a limited degree. At 0.74 the two still catch most of the same waves, so the pair smooths returns a little without insulating either from a shared selloff.
FAQ
What is the correlation between CTS and MDY?
As of 2026-08-27, the correlation of weekly returns between CTS and MDY is 0.74 over 3 years, 0.63 over 1 year and 0.61 over 5 years.
Is MDY a good diversifier for CTS?
To a limited degree. At 0.74 the two still catch most of the same waves, so the pair smooths returns a little without insulating either from a shared selloff.
What does a correlation of 0.74 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/cts-vs-mdy.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/cts-vs-mdy/)
Free with attribution; caching and terms are described in the API documentation.
Related comparisons
Hubs: CTS correlations · MDY correlations
