- ISIN
- US4642885887
- CUSIP
- 464288588
- Issuer
- iShares
- Inception Date
- Mar 16, 2007
- Region
- North America (U.S.)
- Category
- Mortgage Backed Securities
- Leveraged
- 1x (No leverage)
- Index Tracked
- Barclays Capital U.S. MBS Index
- Distribution Policy
- Distributing
- Asset Class
- Bond
- Assets Under Management
- $40B
Share Price Chart
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Performance
MBB Performance Chart
iShares MBS Bond ETF (MBB) is up 0.7% since the beginning of the year. MBB is currently trading at $94 per share. Investors who bought $1,000 worth of MBB shares 5 years ago would now be looking at an investment worth $1,021.
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Returns By Period
iShares MBS Bond ETF (MBB) has returned 0.73% so far this year and 5.95% over the past 12 months. Over the last ten years, MBB has returned 1.29% per year, falling short of the S&P 500 Index benchmark, which averaged 13.88% annually.
iShares MBS Bond ETF
- 1D
- -0.24%
- 1M
- 0.53%
- YTD
- 0.73%
- 6M
- 0.86%
- 1Y
- 5.95%
- 3Y*
- 4.31%
- 5Y*
- 0.42%
- 10Y*
- 1.29%
Benchmark (S&P 500 Index)
- 1D
- -0.37%
- 1M
- -0.01%
- YTD
- 9.16%
- 6M
- 8.64%
- 1Y
- 25.22%
- 3Y*
- 19.78%
- 5Y*
- 11.99%
- 10Y*
- 13.88%
MBB Monthly Returns History
Based on dividend-adjusted daily data since Mar 16, 2007, MBB's average daily return is +0.01%, while the average monthly return is +0.23%. At this rate, an investment would double in approximately 25.1 years.
Historically, 64% of months were positive and 36% were negative. The best month was Nov 2023 with a return of +5.2%, while the worst month was Sep 2022 at -5.1%. The longest winning streak lasted 15 consecutive months, and the longest losing streak was 9 months.
On a daily basis, MBB closed higher 53% of trading days. The best single day was Mar 13, 2020 with a return of +3.1%, while the worst single day was Mar 12, 2020 at -3.2%.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Total | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2026 | 0.49% | 1.63% | -1.69% | 0.17% | 0.36% | -0.22% | 0.73% | ||||||
| 2025 | 0.56% | 2.43% | 0.02% | 0.36% | -0.87% | 1.70% | -0.52% | 1.74% | 1.21% | 0.78% | 0.59% | 0.14% | 8.38% |
| 2024 | -0.30% | -1.70% | 0.88% | -2.82% | 1.96% | 1.21% | 2.64% | 1.74% | 0.94% | -2.78% | 1.51% | -1.76% | 1.31% |
| 2023 | 3.37% | -2.75% | 2.12% | 0.42% | -0.68% | -0.48% | -0.09% | -0.80% | -3.09% | -2.13% | 5.22% | 4.18% | 5.01% |
| 2022 | -1.40% | -1.16% | -2.43% | -3.57% | 1.24% | -1.53% | 3.16% | -3.54% | -5.09% | -1.14% | 4.27% | -0.83% | -11.74% |
| 2021 | 0.15% | -0.86% | -0.49% | 0.58% | -0.30% | -0.01% | 0.52% | -0.02% | -0.35% | -0.27% | -0.24% | -0.13% | -1.43% |
Benchmark Metrics
iShares MBS Bond ETF has an annualized alpha of 2.73%, beta of 0.01, and R2 of 0.00 versus S&P 500 Index. Calculated based on daily prices since March 16, 2007.
- This ETF participates in less of S&P 500 Index's moves in both directions, but captures a larger share of gains (9.80%) than losses (2.85%) - typical of diversified or defensive assets.
- Beta of 0.01 may look defensive, but with R2 of 0.00 this ETF is largely uncorrelated with S&P 500 Index - low beta reflects independence, not downside protection. See the Volatility section for a true picture of this ETF's risk.
- R2 of 0.00 means this ETF moves largely independently of S&P 500 Index - capture ratios reflect limited market correlation rather than active downside protection. Consider using a more representative benchmark.
- Alpha
- 2.73%
- Beta
- 0.01
- R²
- 0.00
- Upside Capture
- 9.80%
- Downside Capture
- 2.85%
Expense Ratio
MBB has an expense ratio of 0.06%, which is considered low.
Return for Risk
Risk / Return Rank
MBB ranks 40 for risk / return — below 40% of ETFs on our site. The returns aren't fully compensating for the risk involved. This isn't necessarily a dealbreaker, but factor it into your decision — especially if you're risk-averse.
Return / Risk — by metrics
The table below present risk-adjusted performance metrics for iShares MBS Bond ETF (MBB) and compare them to S&P 500 Index.
Values are calculated on a 1-year rolling basis and updated daily. Risk-adjusted metrics are more stable over longer periods — use the period switch above to explore them.
| MBB | Benchmark | Difference | |
|---|---|---|---|
| Sharpe ratioReturn per unit of total volatility | -0.69 | ||
| Sortino ratioReturn per unit of downside risk | -0.79 | ||
| Omega ratioGain probability vs. loss probability | 1.24 | 1.37 | -0.13 |
| Calmar ratioReturn relative to maximum drawdown | 2.03 | 2.78 | -0.75 |
| Martin ratioReturn relative to average drawdown | 6.36 | 12.44 | -6.08 |
Dividends
Dividend History
iShares MBS Bond ETF provided a 4.27% dividend yield over the last twelve months, with an annual payout of $4.03 per share. The fund has been increasing its distributions for 4 consecutive years.
| Period | TTM | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dividend | $4.03 | $4.00 | $3.61 | $3.20 | $2.14 | $1.13 | $2.31 | $2.99 | $2.76 | $2.37 | $2.75 | $2.86 |
Dividend yield | 4.27% | 4.21% | 3.94% | 3.40% | 2.31% | 1.05% | 2.10% | 2.77% | 2.64% | 2.23% | 2.58% | 2.66% |
Monthly Dividends
The table displays the monthly dividend distributions for iShares MBS Bond ETF. The dividends shown in the table have been adjusted to account for any splits that may have occurred.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Total | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2026 | $0.00 | $0.33 | $0.33 | $0.33 | $0.33 | $0.33 | $1.66 | ||||||
| 2025 | $0.00 | $0.34 | $0.32 | $0.33 | $0.33 | $0.33 | $0.33 | $0.33 | $0.34 | $0.34 | $0.34 | $0.68 | $4.00 |
| 2024 | $0.00 | $0.30 | $0.29 | $0.28 | $0.28 | $0.30 | $0.31 | $0.31 | $0.32 | $0.31 | $0.31 | $0.60 | $3.61 |
| 2023 | $0.00 | $0.24 | $0.25 | $0.25 | $0.26 | $0.27 | $0.26 | $0.28 | $0.26 | $0.29 | $0.27 | $0.56 | $3.20 |
| 2022 | $0.00 | $0.17 | $0.14 | $0.14 | $0.15 | $0.16 | $0.15 | $0.18 | $0.20 | $0.20 | $0.20 | $0.47 | $2.14 |
| 2021 | $0.00 | $0.19 | $0.20 | $0.19 | $0.16 | $0.13 | $0.10 | $0.08 | $0.07 | $0.02 | $0.00 | $0.00 | $1.13 |
Drawdowns
Drawdowns Chart
The Drawdowns chart displays portfolio losses from any high point along the way. Drawdowns are calculated considering price movements and all distributions paid, if any.
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Worst Drawdowns
The table below displays the maximum drawdowns of the iShares MBS Bond ETF. A maximum drawdown is a measure of risk, indicating the largest reduction in portfolio value due to a series of losing trades.
The maximum drawdown for the iShares MBS Bond ETF was 17.64%, occurring on Oct 19, 2023. Recovery took 507 trading sessions.
The current iShares MBS Bond ETF drawdown is 1.38%.
Related event | Drawdown | Fall | Recovery | Underwater |
|---|---|---|---|---|
2023 correction2023 | -17.64%Oct 2023 | 2y 8mo | 2y 10d | 4y 8moFeb 2021 - Oct 2025 |
2013 pullback2013 | -4.81%Sep 2013 | 11mo 14d | 7mo 28d | 1y 7moSep 2012 - May 2014 |
COVID crash2020 | -4.32%Mar 2020 | 2d | 15d | 17dMar 2020 - Mar 2020 |
Financial crisis2007–2009 | -3.82%Oct 2008 | 1mo 12d | 26d | 2mo 8dSep 2008 - Nov 2008 |
2016 pullback2016 | -3.43%Dec 2016 | 2mo 18d | 8mo 11d | 10mo 29dSep 2016 - Aug 2017 |
Drawdown Indicators
| MBB | Benchmark | Difference | |
|---|---|---|---|
Max DrawdownLargest peak-to-trough decline | -17.64% | -56.78% | +39.14% |
Max Drawdown (1Y)Largest decline over 1 year | -2.94% | -9.10% | +6.16% |
Max Drawdown (3Y)Largest decline over 3 years | -7.68% | -18.90% | +11.22% |
Max Drawdown (5Y)Largest decline over 5 years | -17.19% | -25.43% | +8.24% |
Max Drawdown (10Y)Largest decline over 10 years | -17.64% | -33.92% | +16.28% |
Current DrawdownCurrent decline from peak | -1.38% | -1.80% | +0.42% |
Average DrawdownAverage peak-to-trough decline | -2.34% | -10.71% | +8.37% |
Ulcer IndexDepth and duration of drawdowns from previous peaks | 0.94% | 2.03% | -1.09% |
Volatility
Volatility Chart
The chart below shows the rolling one-month volatility.
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