NBBK vs THFF: Correlation
NB Bancorp, Inc. (NBBK) and First Financial Corporation (THFF) show a strong relationship: their 3-year correlation of weekly returns is 0.77.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are NBBK and THFF?
Across a 3-year window, the weekly returns of NBBK and THFF correlate at 0.77, strong. Little has changed lately, as the 1-year reading of 0.73 lands near the 3-year figure. Stretching to 5 years gives n/a, with an annualized covariance of 598.1 %².
Few assets follow NBBK as closely as THFF, which ranks #2 of 17 tracked partners. Correlation aside, the last 12 months split them widely, with THFF ahead by 19.5 points (+19.3% versus +38.8%).
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.
NBBK vs THFF: side by side
| NBBK (NB Bancorp, Inc.) | THFF (First Financial Corporation) | |
|---|---|---|
| 1-year return | +19.3% | +38.8% |
| 5-year return | n/a | +135.2% |
| Volatility (ann.) | 27.6% | 28.2% |
| Beta vs S&P 500 | 0.84 | 0.81 |
| Max drawdown (3Y) | -24.7% | -20.2% |
| Market cap | $1.0B | $0.9B |
| P/E (trailing) | 14.7 | 11.1 |
| Dividend yield | 4.39% | 2.77% |
| Sector / category | US Listed | US Listed |
Year-by-year returns
| Year | NBBK | THFF |
|---|---|---|
| 2022 | – | +4.4% |
| 2023 | – | -2.6% |
| 2024 | +34.3% | +11.1% |
| 2025 | +10.6% | +36.2% |
| 2026 | +13.9% | +35.0% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are NBBK and THFF good diversifiers for each other?
Only partially. A correlation of 0.77 means NBBK and THFF 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 NBBK and THFF?
As of 2026-08-27, the correlation of weekly returns between NBBK and THFF is 0.77 over 3 years, 0.73 over 1 year and n/a over 5 years.
Is THFF a good diversifier for NBBK?
Only partially. A correlation of 0.77 means NBBK and THFF share most of their swings. Pairing them dampens volatility somewhat, but it will not protect against a common drawdown.
What does a correlation of 0.77 mean?
On the −1 to +1 scale, 0.77 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/nbbk-vs-thff.json
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Hubs: NBBK correlations · THFF correlations
