PDFS vs UCTT: Correlation
How closely do PDF Solutions, Inc. (PDFS) and Ultra Clean Holdings, Inc. (UCTT) trade together? Their weekly returns over three years give a correlation of 0.70, which is strong.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are PDFS and UCTT?
On 3 years of weekly data the PDFS/UCTT correlation comes out at 0.70, strong. The relationship has been stable: the 1-year correlation (0.67) sits close to the 3-year figure. The 5-year figure is 0.63, and annualized covariance runs at 2077.5 %².
UCTT is one of the assets that tracks PDFS most closely: it ranks #2 out of the 16 assets we track against PDFS. Correlation aside, the last 12 months split them widely, with UCTT ahead by 78.0 points (+133.6% versus +211.6%).
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.
PDFS vs UCTT: side by side
| PDFS (PDF Solutions, Inc.) | UCTT (Ultra Clean Holdings, Inc.) | |
|---|---|---|
| 1-year return | +133.6% | +211.6% |
| 5-year return | +105.9% | +57.9% |
| Volatility (ann.) | 47.4% | 62.8% |
| Beta vs S&P 500 | 1.55 | 2.28 |
| Max drawdown (3Y) | -58.5% | -68.2% |
| Market cap | $1.9B | $3.4B |
| P/E (trailing) | 177.5 | – |
| Dividend yield | 0.00% | 0.00% |
| Sector / category | US Listed | US Listed |
Year-by-year returns
| Year | PDFS | UCTT |
|---|---|---|
| 2022 | -10.3% | -42.2% |
| 2023 | +12.7% | +3.0% |
| 2024 | -15.7% | +5.3% |
| 2025 | +5.4% | -29.5% |
| 2026 | +61.8% | +195.1% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are PDFS and UCTT good diversifiers for each other?
Only partially. A correlation of 0.70 means PDFS and UCTT share most of their swings. Pairing them dampens volatility somewhat, but it will not protect against a common drawdown.
FAQ
What is the correlation between PDFS and UCTT?
Using weekly returns as of 2026-08-27: 0.70 over 3 years, with 0.67 over the last year and 0.63 over 5 years.
Is UCTT a good diversifier for PDFS?
Only partially. A correlation of 0.70 means PDFS and UCTT share most of their swings. Pairing them dampens volatility somewhat, but it will not protect against a common drawdown.
What does a correlation of 0.70 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
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Related comparisons
Hubs: PDFS correlations · UCTT correlations
