MDY vs NTCT: Correlation
Measured on weekly returns over the past three years, SPDR S&P MidCap 400 ETF (MDY) and NetScout Systems, Inc. (NTCT) carry a correlation of 0.48, a moderate link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are MDY and NTCT?
Over the past 3 years, MDY and NTCT moved with a correlation of 0.48, which is moderate. The past 12 months show a weaker link (0.20) than the 3-year average (0.48). Over 5 years the correlation is 0.44, and the annualized covariance of weekly returns is 240.7 %².
Within MDY's tracked universe of 359 assets, NTCT comes in at #316 by 3-year correlation. Correlation aside, the last 12 months split them widely, with NTCT ahead by 41.1 points (+18.3% versus +59.4%). One caveat on sizing: NTCT is 1.8 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.
MDY vs NTCT: side by side
| MDY (SPDR S&P MidCap 400 ETF) | NTCT (NetScout Systems, Inc.) | |
|---|---|---|
| 1-year return | +18.3% | +59.4% |
| 5-year return | +47.5% | +42.7% |
| Volatility (ann.) | 16.5% | 30.4% |
| Beta vs S&P 500 | 0.91 | 0.85 |
| Max drawdown (3Y) | -24.0% | -38.4% |
| Market cap | – | $2.9B |
| P/E (trailing) | – | 23.5 |
| Dividend yield | 1.02% | 0.00% |
| Expense ratio | 0.23% | – |
| Assets under management | $26.5B | – |
| Sector / category | ETF · US Small & Mid Cap | US Listed |
On the fund side, MDY sits in the Mid-Cap Blend category at State Street Investment Management, with $26.5B under management, 400 holdings, a 0.23% expense ratio, a 1.02% trailing dividend yield.
Year-by-year returns
| Year | MDY | NTCT |
|---|---|---|
| 2022 | -13.3% | -1.7% |
| 2023 | +16.1% | -32.5% |
| 2024 | +13.6% | -1.3% |
| 2025 | +7.2% | +24.9% |
| 2026 | +16.4% | +45.8% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are MDY and NTCT good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.48 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between MDY and NTCT?
Using weekly returns as of 2026-08-27: 0.48 over 3 years, with 0.20 over the last year and 0.44 over 5 years.
Is NTCT a good diversifier for MDY?
Yes, to a useful degree: a correlation of 0.48 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.48 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/mdy-vs-ntct.json
Drop this badge in a README or notebook; it updates with the data:
[](https://www.pairbook.io/pair/mdy-vs-ntct/)
No key needed, free to use. Full endpoint list in the API documentation.
Related comparisons
Hubs: MDY correlations · NTCT correlations
