IEF vs NBB: Correlation
How closely do iShares 7-10 Year Treasury Bond ETF (IEF) and Nuveen Taxable Municipal Income Fund (NBB) trade together? Their weekly returns over three years give a correlation of 0.71, which is strong.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are IEF and NBB?
Over the past 3 years, IEF and NBB moved with a correlation of 0.71, which is strong. The link has loosened recently: the 1-year correlation (0.57) runs below the 3-year figure (0.71). Over 5 years the correlation is 0.65, and the annualized covariance of weekly returns is 55.1 %².
Among the 48 assets we track against IEF, NBB ranks #10 by 3-year correlation. Twelve-month performance is nearly a tie, at +0.9% for IEF and +5.3% for NBB. Risk is not evenly split, since NBB carries 1.8 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.
IEF vs NBB: side by side
| IEF (iShares 7-10 Year Treasury Bond ETF) | NBB (Nuveen Taxable Municipal Income Fund) | |
|---|---|---|
| 1-year return | +0.9% | +5.3% |
| 5-year return | -7.9% | -5.4% |
| Volatility (ann.) | 6.5% | 12.0% |
| Beta vs S&P 500 | 0.04 | 0.22 |
| Max drawdown (3Y) | -6.9% | -11.4% |
| Market cap | – | – |
| P/E (trailing) | – | 16.4 |
| Dividend yield | 3.96% | 0.00% |
| Expense ratio | 0.15% | – |
| Assets under management | $47.2B | – |
| Sector / category | ETF · Bonds | US Listed |
IEF is a Long Government fund from iShares: $47.2B under management, a 0.15% expense ratio, a 3.96% trailing dividend yield.
Year-by-year returns
| Year | IEF | NBB |
|---|---|---|
| 2022 | -15.2% | -24.6% |
| 2023 | +3.6% | +7.6% |
| 2024 | -0.6% | +1.4% |
| 2025 | +8.0% | +13.6% |
| 2026 | -0.8% | +2.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are IEF and NBB good diversifiers for each other?
Somewhat, no more. With 0.71 correlation, most large moves hit both names, and the diversification benefit stays modest.
FAQ
What is the correlation between IEF and NBB?
The IEF/NBB correlation stands at 0.71 on a 3-year window (1 year: 0.57, 5 years: 0.65), computed from weekly returns as of 2026-08-27.
Is NBB a good diversifier for IEF?
Somewhat, no more. With 0.71 correlation, most large moves hit both names, and the diversification benefit stays modest.
What does a correlation of 0.71 mean?
On the −1 to +1 scale, 0.71 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/ief-vs-nbb.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/ief-vs-nbb/)
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Related comparisons
Hubs: IEF correlations · NBB correlations
