ACH vs PDM: Correlation
Accendra Health, Inc. (ACH) and Piedmont Realty Trust, Inc. (PDM) 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 ACH and PDM?
Over the past 3 years, ACH and PDM moved with a correlation of 0.41, which is moderate. Little has changed lately, as the 1-year reading of 0.37 lands near the 3-year figure. Over 5 years the correlation is 0.41, and the annualized covariance of weekly returns is 1289.9 %².
Among the 16 assets we track against ACH, PDM ranks #5 by 3-year correlation. The last year tells two different stories: PDM led by 91.3 percentage points, -75.3% for ACH against +16.0% for PDM. Risk is not evenly split, since ACH carries 2.5 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.
ACH vs PDM: side by side
| ACH (Accendra Health, Inc.) | PDM (Piedmont Realty Trust, Inc.) | |
|---|---|---|
| 1-year return | -75.3% | +16.0% |
| 5-year return | -96.8% | -29.9% |
| Volatility (ann.) | 89.1% | 35.3% |
| Beta vs S&P 500 | 1.37 | 0.95 |
| Max drawdown (3Y) | -96.6% | -46.4% |
| Market cap | $0.1B | $1.2B |
| P/E (trailing) | – | – |
| Dividend yield | 0.00% | 0.00% |
| Sector / category | US Listed | US Listed |
Year-by-year returns
| Year | ACH | PDM |
|---|---|---|
| 2022 | -55.1% | -46.8% |
| 2023 | -1.3% | -14.8% |
| 2024 | -32.2% | +37.2% |
| 2025 | -78.6% | -7.3% |
| 2026 | -56.8% | +16.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are ACH and PDM good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.41 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between ACH and PDM?
The ACH/PDM correlation stands at 0.41 on a 3-year window (1 year: 0.37, 5 years: 0.41), computed from weekly returns as of 2026-08-27.
Is PDM a good diversifier for ACH?
Yes, to a useful degree: a correlation of 0.41 leaves real independence between the two, which historically damped combined volatility.
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.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/ach-vs-pdm.json
Embed this badge (it refreshes with the data), with attribution:
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Related comparisons
Hubs: ACH correlations · PDM correlations
