iSharesGovernment Mortgage-Backed BondMBB · Nasdaq

iShares MBS ETF (MBB)

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Price: $92.05; —30 Oct 2026
Assets: $36.2B; Total net assets
Expense ratio: 0.04%; Category 0.82%
Yield: 4.51%; Trailing distributions

1Y return: 0.6%0.0%; Category 0.6%
3Y CAGR: 6.4%+0.3%; Category 6.1%
5Y CAGR: 0.3%-0.1%; Category 0.3%

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iShares MBS ETF

Calendar-year returns

Fund only: no comparison series covers this fund's history.

Risk statistics

Five years of daily closes. Risk-free rate 4% a year.

Standard deviation: —
Maximum drawdown: —
Sharpe ratio: —
Sortino ratio: —
Beta: —
Alpha: —
R²: —
Information ratio: —
Upside capture: —
Downside capture: —
Tracking error: —

Trailing returns compared with benchmark
Period	1M	3M	6M	YTD	1Y	3YCAGR	5YCAGR	10YCAGR	LaunchCAGR
ETF	+3.1%	+0.2%	-0.8%	-0.1%	+0.6%	+6.4%	+0.3%	+1.2%	+2.6%
Government Mortgage-Backed Bond average	2.8%	-0.1%	-1.0%	-0.2%	0.6%	6.1%	0.3%	1.2%	2.0%
Difference	+0.3%	+0.3%	+0.2%	0.0%	0.0%	+0.3%	-0.1%	0.0%	+0.5%

Holdings

The 1 largest positions make up 6.5% of the fund.

Top holdings

Largest holdings by weight
Ticker	Holding	Weight
BISXX	BlackRock Cash Funds Instl SL Agency	6.49%

Credit quality

Share of the bonds by rating.

AA100.0%

Asset mix

Bonds99.5%
Cash0.5%

ETF details

Issuer: iShares
Category: Fixed Income · Government Mortgage-Backed Bond
Ticker: MBB
Exchange: Nasdaq
Inception: 13 Mar 2007 (19.6 years)
Structure: Exchange Traded Fund
Expense ratio: 0.04% (category 0.82%)
Holdings turnover: 153% (category 321%)
Distribution yield: 4.51%
Beta, 3 years: 1.14
Total net assets: $36.2B
Average duration: 3.76 years
Average maturity: 8.75 years

Prices and returns as of 30 Oct 2026; total return with distributions reinvested, before brokerage and taxes. Not investment advice.

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