CSGP vs MAIN: Correlation
How closely do CoStar Group (CSGP) and Main Street Capital Corporation (MAIN) trade together? Their weekly returns over three years give a correlation of 0.45, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are CSGP and MAIN?
Across a 3-year window, the weekly returns of CSGP and MAIN correlate at 0.45, moderate. Little has changed lately, as the 1-year reading of 0.46 lands near the 3-year figure. Stretching to 5 years gives 0.42, with an annualized covariance of 323.5 %².
Among the 34 assets we track against CSGP, MAIN ranks #9 by 3-year correlation. The last year tells two different stories: MAIN led by 62.5 percentage points, -65.0% for CSGP against -2.5% for MAIN. One caveat on sizing: CSGP is 1.9 times as volatile as the other leg, so an equal-dollar split is far from equal-risk.
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.
CSGP vs MAIN: side by side
| CSGP (CoStar Group) | MAIN (Main Street Capital Corporation) | |
|---|---|---|
| 1-year return | -65.0% | -2.5% |
| 5-year return | -62.7% | +106.5% |
| Volatility (ann.) | 36.5% | 19.6% |
| Beta vs S&P 500 | 0.86 | 0.69 |
| Max drawdown (3Y) | -72.2% | -22.4% |
| Market cap | $12.7B | $5.5B |
| P/E (trailing) | 174.1 | 11.7 |
| Dividend yield | 0.00% | 5.29% |
| Sector / category | Real Estate | US Listed |
Year-by-year returns
| Year | CSGP | MAIN |
|---|---|---|
| 2022 | -2.2% | -11.4% |
| 2023 | +13.1% | +28.2% |
| 2024 | -18.1% | +47.3% |
| 2025 | -6.1% | +10.7% |
| 2026 | -53.4% | +1.9% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are CSGP and MAIN good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.45 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between CSGP and MAIN?
The CSGP/MAIN correlation stands at 0.45 on a 3-year window (1 year: 0.46, 5 years: 0.42), computed from weekly returns as of 2026-08-27.
Is MAIN a good diversifier for CSGP?
Yes, to a useful degree: a correlation of 0.45 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.45 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
$ curl https://www.pairbook.io/api/v1/pairs/csgp-vs-main.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/csgp-vs-main/)
The core API is free. Terms and every endpoint in the API documentation.
Related comparisons
Hubs: CSGP correlations · MAIN correlations
