PETS vs PLAB: Correlation
PetMed Express, Inc. (PETS) and Photronics, Inc. (PLAB) show a moderate relationship: their 3-year correlation of weekly returns is 0.41.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are PETS and PLAB?
Over the past 3 years, PETS and PLAB moved with a correlation of 0.41, which is moderate. The past 12 months show a tighter link (0.56) than the 3-year average (0.41). Over 5 years the correlation is 0.36, and the annualized covariance of weekly returns is 1790.4 %².
Within PETS's tracked universe of 10 assets, PLAB comes in at #5 by 3-year correlation. The last year tells two different stories: PLAB led by 67.7 percentage points, -41.5% for PETS against +26.2% for PLAB.
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.
PETS vs PLAB: side by side
| PETS (PetMed Express, Inc.) | PLAB (Photronics, Inc.) | |
|---|---|---|
| 1-year return | -41.5% | +26.2% |
| 5-year return | -92.7% | +106.4% |
| Volatility (ann.) | 72.9% | 60.0% |
| Beta vs S&P 500 | 1.10 | 1.56 |
| Max drawdown (3Y) | -86.3% | -50.6% |
| Market cap | – | $1.8B |
| P/E (trailing) | – | 10.8 |
| Dividend yield | 0.00% | 0.00% |
| Sector / category | US Listed | US Listed |
Year-by-year returns
| Year | PETS | PLAB |
|---|---|---|
| 2022 | -25.8% | -10.7% |
| 2023 | -54.8% | +86.4% |
| 2024 | -36.2% | -24.9% |
| 2025 | -33.6% | +35.8% |
| 2026 | -42.2% | -5.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are PETS and PLAB good diversifiers for each other?
Reasonably. At 0.41, PETS and PLAB keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
FAQ
What is the correlation between PETS and PLAB?
The PETS/PLAB correlation stands at 0.41 on a 3-year window (1 year: 0.56, 5 years: 0.36), computed from weekly returns as of 2026-08-27.
Is PLAB a good diversifier for PETS?
Reasonably. At 0.41, PETS and PLAB keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
What does a correlation of 0.41 mean?
A reading of 0.41 sits on a scale from −1 (opposite moves) through 0 (unrelated) to +1 (identical moves). Correlation captures direction, not magnitude or performance.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/pets-vs-plab.json
Drop this badge in a README or notebook; it updates with the data:
[](https://www.pairbook.io/pair/pets-vs-plab/)
No key needed, free to use. Full endpoint list in the API documentation.
Related comparisons
Hubs: PETS correlations · PLAB correlations
