PRLB vs SPY: Correlation
Measured on weekly returns over the past three years, Proto Labs, Inc. (PRLB) and SPDR S&P 500 ETF Trust (SPY) carry a correlation of 0.44, a moderate link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are PRLB and SPY?
On 3 years of weekly data the PRLB/SPY correlation comes out at 0.44, moderate. Recent behaviour matches the longer record: 0.37 over 1 year against 0.44 over 3. The 5-year figure is 0.42, and annualized covariance runs at 318.0 %².
By 3-year correlation, SPY places #9 of the 17 assets tracked against PRLB. Their recent paths diverged sharply: over the last 12 months PRLB outperformed by 37.0 percentage points (+57.6% for PRLB against +20.6% for SPY). Risk is not evenly split, since PRLB carries 3.5 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.
PRLB vs SPY: side by side
| PRLB (Proto Labs, Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +57.6% | +20.6% |
| 5-year return | +10.1% | +82.4% |
| Volatility (ann.) | 50.3% | 14.5% |
| Beta vs S&P 500 | 1.52 | 1.00 |
| Max drawdown (3Y) | -33.6% | -18.8% |
| Market cap | $1.9B | – |
| P/E (trailing) | 62.6 | – |
| 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 | PRLB | SPY |
|---|---|---|
| 2022 | -50.3% | -18.2% |
| 2023 | +52.6% | +26.2% |
| 2024 | +0.3% | +24.9% |
| 2025 | +29.4% | +17.7% |
| 2026 | +58.3% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are PRLB and SPY good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.44 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between PRLB and SPY?
Using weekly returns as of 2026-08-27: 0.44 over 3 years, with 0.37 over the last year and 0.42 over 5 years.
Is SPY a good diversifier for PRLB?
Yes, to a useful degree: a correlation of 0.44 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.44 mean?
On the −1 to +1 scale, 0.44 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: PRLB correlations · SPY correlations
