NTCT vs SPY: Correlation
Measured on weekly returns over the past three years, NetScout Systems, Inc. (NTCT) and SPDR S&P 500 ETF Trust (SPY) carry a correlation of 0.41, a moderate link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are NTCT and SPY?
On 3 years of weekly data the NTCT/SPY correlation comes out at 0.41, moderate. The past 12 months show a weaker link (0.20) than the 3-year average (0.41). The 5-year figure is 0.38, and annualized covariance runs at 178.3 %².
Among the 13 assets we track against NTCT, SPY ranks #8 by 3-year correlation. The last year tells two different stories: NTCT led by 38.8 percentage points, +59.4% for NTCT against +20.6% for SPY. Risk is not evenly split, since NTCT 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.
NTCT vs SPY: side by side
| NTCT (NetScout Systems, Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +59.4% | +20.6% |
| 5-year return | +42.7% | +82.4% |
| Volatility (ann.) | 30.4% | 14.5% |
| Beta vs S&P 500 | 0.85 | 1.00 |
| Max drawdown (3Y) | -38.4% | -18.8% |
| Market cap | $2.9B | – |
| P/E (trailing) | 23.5 | – |
| Dividend yield | 0.00% | 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 | NTCT | SPY |
|---|---|---|
| 2022 | -1.7% | -18.2% |
| 2023 | -32.5% | +26.2% |
| 2024 | -1.3% | +24.9% |
| 2025 | +24.9% | +17.7% |
| 2026 | +45.8% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are NTCT and SPY good diversifiers for each other?
A fair diversifier. At 0.41, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
FAQ
What is the correlation between NTCT and SPY?
Using weekly returns as of 2026-08-27: 0.41 over 3 years, with 0.20 over the last year and 0.38 over 5 years.
Is SPY a good diversifier for NTCT?
A fair diversifier. At 0.41, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
What does a correlation of 0.41 mean?
On the −1 to +1 scale, 0.41 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.
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Related comparisons
Hubs: NTCT correlations · SPY correlations
